A Host of things today

[movietvet]

I was at my fav taco place for Taco Thursday. My girl, Linda" calls and said the TB will not start/turnover. Said she could not even turn the key off and remove the key and all of the dash was dead. Dealing with a 2002 TB LS, 4.2, bone stock as they come.

I hurried home and verified her concern. No lights on at dash or at headlights or anywhere. First thing I did was attach my battery charger to it and after 5 minutes on the "blast charge" it fired right up and was able to shut off and remove the key. I shut the charger off and then the engine turned over slow and engine would not fire off.

I then turned the charger on and did a slow charge for 1 hour. I then verified a 13.9 volt battery on my DVOM. Then did a load test and under full load for 15 seconds, the battery held 11.4 volts. Good battery. I then attached my Power Probe DRAW tester and then removed cables from battery. Key was off and out of the ignition. The systems started shutting down/going to sleep and in the end, I had a very steady 14ma draw for 15 minutes.

I have a feeling that I have an intermittent draw from the under hood light. I unplugged it for now. I will be monitoring it and report back if any further problems.

During all this, I noticed the "Change Engine Oil" light would stay on for approximately 10 seconds after engine started. Did not do this before the battery problem. I checked oil. Was full of very clean 5w-30 Valvoline R&P oil and I looked at the sticker I put up on the windshield corner. Next due time is 7-7-26 at 82K miles, whichever come first. I always write the sticker up for 4 months or 4k miles, whichever is first. I did 3 different resets on the light. KOEO and depress pedal all the way to floor, 3 times in 5 seconds and the Key Off. The light is still staying on after system checks after start engine but only for about 10 seconds.

Next, and last but not least. What is the red light, to the right of the tune knob, on the radio? It flashes about every 3 seconds when the key is off and then will flash at a much longer interval when engine is running. I looked in owner's manual but could not find a definitive answer.

By the way, this TB does not have key fobs. It is a very basic with no module for use of keys fobs and does not have the RPO code for the key fobs/module.

See Pics:

 

[movietvet]

Edit for above post: The slow flashing red light, next to the TUNE knob on the radio, will always flash, key in ignition or not, unless the engine is started. The rest of the time, it has the slow red light flash.

I must have a very good camera in my phone. The pics look like the vehicle is dirty, it is not dirty at all. We take care of the vehicles. LOL!!!

 

[TollKeeper]

That light is to indicate to potential thieves that the radio has a VIN lock if stolen.

The draw, mine doesnt have a hood light, so....

I know the ignition switch can do it, and also the RAP door latches.

 

[movietvet]

I found this about the flashing red light and is a long version of what @TollKeeper said:

Red Flashing Light on 2002 Chevy Trailblazer Radio​

On a 2002 Chevy Trailblazer, the red flashing light to the right of the radio tuner knob is part of the vehicle’s radio security system. It’s designed to indicate that the radio is locked to a specific key or key fob, and it will flash when the ignition is off and the vehicle is armed Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.

Why it happens​

• Key fob or key chip recognition: Starting around 2001–2002, GM began using a chip in the key to authenticate it. If the vehicle’s computer doesn’t recognize the key, it will lock the radio and trigger the flashing light Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.
• Arming the vehicle: When you lock the doors with the key fob, the system may briefly flash the light to confirm the key is valid.
• Key replacement or damage: If you’ve used a generic or copied key, or if the original key’s chip is damaged, the system may not recognize it, causing the light to flash and preventing the car from starting Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.

What it means for starting​

If the light flashes only when the key is out of the ignition, it’s a sign the system is waiting for a valid key. If you try to start with a non-recognized key, the engine may not crank or may start and then shut off as a security measure Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.

How to fix or turn it off​

1. Use the original key with the chip — generic keys may not work.
2. Have the key reprogrammed at a GM dealer or authorized service center. This ensures the radio and ignition systems recognize the key.
3. Check the key fob battery — a weak battery can cause recognition issues.
4. If the light is just a cosmetic indicator (not affecting start), it may be a design quirk and won’t stop the car from starting, but it will still lock the radio until the key is recognized.

Safety note​

Do not bypass the security light — it’s part of the anti-theft system. If you need to start the car with a non-recognized key, you’ll need to have it reprogrammed to avoid repeated lockouts.

Bottom line: The red flashing light is a radio security indicator tied to your key’s chip. If it only flashes when the key is out, it’s likely a recognition issue. Use the original key or have it reprogrammed to restore normal operation Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum. JustAnswer

 

[movietvet]

That light is to indicate to potential thieves that the radio has a VIN lock if stolen.

The draw, mine doesnt have a hood light, so....

I know the ignition switch can do it, and also the RAP door latches.

What are RAP door latches?

I have unhooked the under hood light. I had a draw problem before and it WAS the under hood light that caused it. Maybe the new light I got, to replace the old one, is also a dud? I had the new under hood light disconnected when I did the Power Probe DRAW testing.

 

[movietvet]

@TollKeeper, any insight on the "Change Engine Oil" light?

 

[TollKeeper]

What are RAP door latches?

I have unhooked the under hood light. I had a draw problem before and it WAS the under hood light that caused it. Maybe the new light I got, to replace the old one, is also a dud? I had the new under hood light disconnected when I did the Power Probe DRAW testing.

Retained Access Power. Where it leaves the power on to the radio, and other interior amenities until a door is opened. There is a Microswitch in front door latches (both sides) that are known to go bad, and can/will cause a battery to flat line. I think its also in the back door latches, but dont know that for sure. On the GMT800 it is, not sure on the GMT360.

@TollKeeper, any insight on the "Change Engine Oil" light?

This one I have no insight on. Sorry.

 

[movietvet]

Does this make sense?

Resetting the “Change Engine Oil” Light on a 2002 Chevy Trailblazer​

If your 2002 Chevy Trailblazer’s oil change light stays on for 2–3 minutes after starting the engine, it usually means the oil life system hasn’t been reset after your oil change. The system uses an algorithm based on engine speed, temperature, and driving conditions to estimate oil degradation, so you must reset it to get accurate readings erthie.com.

Standard Reset Procedure (No Driver Information Center)​

1. Turn the ignition to “RUN” (do not start the engine) Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum+1.
2. Press and release the gas pedal 3 times — all the way down — within about 5 seconds Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum+1.
3. Start the engine and check the dash. If the light flashes or goes out, the reset is complete Let's Fix That Car.
4. If it doesn’t reset, try slower pedal presses within the 5-second window — some owners report success with this variation Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.
5. If it still won’t reset, repeat the process a few times; it can take multiple attempts Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.

Alternative Reset (With Driver Information Center)​

If your 2002 Trailblazer has the DIC (driver info display) on the lower dash:

1. Turn ignition to “ON” without starting the engine Answers.
2. Use the menu/fuel icon button to navigate to the Oil Life Remaining display.
3. Press and hold the SET/RESET or arrow button until the oil life percentage starts flashing.
4. Press again to confirm reset to 100% erthie.com+1.
5. Start the engine and verify the light is gone.

Tips​

• Always reset the system immediately after an oil change to avoid the light staying on for long periods erthie.com.
• If the light persists after multiple resets, check for diagnostic trouble codes with an OBD-II scanner, as a malfunctioning sensor or code could be keeping the system active Answers.
• Disconnecting the battery for 10–15 minutes can sometimes reset the system, but this is less reliable and may clear other settings Answers.

By following the correct reset method for your model year and setup, you should be able to clear the oil change light and get accurate maintenance reminders.

 

[movietvet]

Just got back from a 25 mile round trip. Started right up, each time and no problems or warning lights.

 

[Mooseman]

I found this about the flashing red light and is a long version of what @TollKeeper said:

Red Flashing Light on 2002 Chevy Trailblazer Radio​

On a 2002 Chevy Trailblazer, the red flashing light to the right of the radio tuner knob is part of the vehicle’s radio security system. It’s designed to indicate that the radio is locked to a specific key or key fob, and it will flash when the ignition is off and the vehicle is armed Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.

Why it happens​

• Key fob or key chip recognition: Starting around 2001–2002, GM began using a chip in the key to authenticate it. If the vehicle’s computer doesn’t recognize the key, it will lock the radio and trigger the flashing light Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.
• Arming the vehicle: When you lock the doors with the key fob, the system may briefly flash the light to confirm the key is valid.
• Key replacement or damage: If you’ve used a generic or copied key, or if the original key’s chip is damaged, the system may not recognize it, causing the light to flash and preventing the car from starting Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.

What it means for starting​

If the light flashes only when the key is out of the ignition, it’s a sign the system is waiting for a valid key. If you try to start with a non-recognized key, the engine may not crank or may start and then shut off as a security measure Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum.

How to fix or turn it off​

1. Use the original key with the chip — generic keys may not work.
2. Have the key reprogrammed at a GM dealer or authorized service center. This ensures the radio and ignition systems recognize the key.
3. Check the key fob battery — a weak battery can cause recognition issues.
4. If the light is just a cosmetic indicator (not affecting start), it may be a design quirk and won’t stop the car from starting, but it will still lock the radio until the key is recognized.

Safety note​

Do not bypass the security light — it’s part of the anti-theft system. If you need to start the car with a non-recognized key, you’ll need to have it reprogrammed to avoid repeated lockouts.

Bottom line: The red flashing light is a radio security indicator tied to your key’s chip. If it only flashes when the key is out, it’s likely a recognition issue. Use the original key or have it reprogrammed to restore normal operation Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum. JustAnswer

Just some clarifications:

They were wrong back then and is still wrong. Our trucks do not have chips in the keys. They use what's called Passlock. It uses a sensor in the lock cylinder to detect if it was damaged (I. e. Pried off). The only exception is the Saab 9-7x that uses chips with the PassKey 3 system.

The red light in the radio I can't see as being related to the key security system. It's more a dummy security light for would be thieves (which I don't understand why anyone would want to steal it even when it was new ), especially since there is a dedicated security light in the cluster if there is a problem with the key.

Retained Access Power. Where it leaves the power on to the radio, and other interior amenities until a door is opened. There is a Microswitch in front door latches (both sides) that are known to go bad, and can/will cause a battery to flat line. I think its also in the back door latches, but dont know that for sure. On the GMT800 it is, not sure on the GMT360.

It does go out after 10 minutes by design to preserve battery power unless the BCM is having issues with it. It shouldn't kill the battery either way.

 

[budwich]

Just got back from a 25 mile round trip. Started right up, each time and no problems or warning lights.

what was the "charging voltage" during that "run"?

 

[movietvet]

Just some clarifications:

They were wrong back then and is still wrong. Our trucks do not have chips in the keys. They use what's called Passlock. It uses a sensor in the lock cylinder to detect if it was damaged (I. e. Pried off). The only exception is the Saab 9-7x that uses chips with the PassKey 3 system.

The red light in the radio I can't see as being related to the key security system. It's more a dummy security light for would be thieves (which I don't understand why anyone would want to steal it even when it was new ), especially since there is a dedicated security light in the cluster if there is a problem with the key.

It does go out after 10 minutes by design to preserve battery power unless the BCM is having issues with it. It shouldn't kill the battery either way.

The only thing I doubted about the found info was the "chip" in the key. We had extra keys cut and one is in a magnetic box on the rear frame. I know that key works/starts the engine.

I have locked the TB and stood watch on the red light and saw it slow way down to 6-7 seconds between flashes but never stood watch long enough to see if it went completely out.

When I had the steady 14ma draw for 15 minutes, to tell you the truth, I never looked to see if the red light was flashing. Since I knew the light flash interval slowed down, when I was watching it without the Power Probe DRAW attached, I assumed it was not part of the problem.

Hope you get the hell out of that hospital today. Lot's of sick people in there, ya know...

 

[movietvet]

We had the a/c on and radio and according to the gauge, it was either right at 14 volts or a needles width below or above the 14 volt mark.

 

[movietvet]

She drove the dogs back home yesterday afternoon and then went to a local store and then back home, with no problems.

Going back this morning to get dogs for the entire day and she will be going alone. I am 50/50 on the under hood light being the problem.

 

[dhanger]

I hate it when electrical gremlins show up on these newer cars (by newer I mean anything late 90's and newer when computers started taking over), it's one of my weak points of troubleshooting. I can't imagine the nightmare of trying to troubleshoot the latest models and their way overused mountains of silicon. One of the reasons I won't buy anything new--I won't pay for tons of stuff I don't want or need and have to have a computer scientist on hand to fix the many things that will go wrong.

 

[budwich]

We had the a/c on and radio and according to the gauge, it was either right at 14 volts or a needles width below or above the 14 volt mark.

how old is the battery... did you check the cell levels? how old is the alternator?

 

[movietvet]

Unknown alternator age, we bought the TB in 2022. Battery bought in January of 2023. Sealed battery.
Has passed 2 separate load tests. It is an Interstate MT78 5 year battery.

On my 2005 Tahoe Z71, I recently had a battery failure on an Interstate AGM 5 year battery that was bought in June 2021. It was bad enough, the battery would not take a jump or battery charge.

New battery and those problems are solved. I may just go ahead and replace the TB 3.5 years old battery. Since I did have the TB problem, I did my alternator tests and mechanical ear listened for bearing noise and there is nothing but smooth noise at different speeds.

She does not put miles on that TB. Bought it in June of 2022 with 74k miles and now has 78k miles.

 

[budwich]

Unknown alternator age, we bought the TB in 2022. Battery bought in January of 2023. Sealed battery.
Has passed 2 separate load tests. It is an Interstate MT78 5 year battery.

I am not a battery expert but I don't believe your battery is a "sealed battery" as there are very few maker's / model of "flooded" batteries that are "sealed". The "caps" are not the tradional style but the "panel" of three cells can be opened to check fluid levels with a "hydrometer".

In terms of the "charge voltage", it seems to be somewhat low (if you came from a "dead' battery state) and only did a slow charge for "1 hour". Relying on the dash gage for volts is not very reliable.

How was the battery connections in terms of tightness and cleanness?

Anyway, perhaps you just have a "drain" but I would be surprised if it was the hood light... I guess that would point to the contact somewhere not functioning.

 

[movietvet]

The "Change Engine Oil" light now goes out faster, as it should, after the self checks. I did the reset on the light, at a slower pace of 3 gas pedals to the floor with KOEO.

 

[movietvet]

what was the "charging voltage" during that "run"?

how old is the battery... did you check the cell levels? how old is the alternator?

I am not a battery expert but I don't believe your battery is a "sealed battery" as there are very few maker's / model of "flooded" batteries that are "sealed". The "caps" are not the tradional style but the "panel" of three cells can be opened to check fluid levels with a "hydrometer".

In terms of the "charge voltage", it seems to be somewhat low (if you came from a "dead' battery state) and only did a slow charge for "1 hour". Relying on the dash gage for volts is not very reliable.

How was the battery connections in terms of tightness and cleanness?

Anyway, perhaps you just have a "drain" but I would be surprised if it was the hood light... I guess that would point to the contact somewhere not functioning.

Battery is 3.5 years old. I did not look for a way to openings for cell access. Charging voltage was constant between 13.9 and 14.2 volts.

I had a battery draw problem on this before and it was the under hood light. I changed the light and after that no problems till this time. I unplugged the light and all good for now.

The battery cable connections are absolutely tight and no corrosion AT ALL.

 

[AmpOverload]

The "Change Engine Oil" light now goes out faster, as it should, after the self checks. I did the reset on the light, at a slower pace of 3 gas pedals to the floor with KOEO.

Just curious... Did the "CHANGE ENG OIL" lamp flash after you did the reset?

Based on my experience with resetting the 'engine oil life' on GM vehicles, I would expect that the "CHANGE ENG OIL" lamp would flash (about 5 times) after a successful pedal-induced reset operation. However, my notes show that on at least one GM vehicle (and maybe many others), the flashing doesn't begin until about 4 or 5 seconds after the 3rd press/release of the pedal, so it can be really easy to miss it if you're not watching for it at the right time!

If you don't use the "CHANGE ENG OIL" lamp (or, for those who can display it, the actual "engine oil life remaining" value) to decide when to change your oil, then there's no harm in doing another reset at any time, of course. I've found that I can repeatedly do the "3 pedal push+release" reset operation any number of times, as long as I cycle the ignition key back off then on first.

Of course, even on GM vehicles without the Driver Information Center (DIC), you should be able to query the 'engine oil life remaining' value directly from the PCM, using a Tech2 or Tech2Win or, failing that, even by using a cheap scantool with an Android app like "Torque Pro" or "Car Scanner" and a custom PID (typically Mode $22, PID $119F, formula "A/255*100", in units of "percent"). For those with such capability, it's the best way to know for sure if the "life" was properly reset.

 

[movietvet]

IIRC, on the TB, the Change Engine Oil light is lit up when the engine is started, just like a CEL, and then goes out when engine is running and the you let go of the key. Before I did the slower 3 pedal push to floor trick, the Change Engine Oil, after the engine was running it would take 5-7 seconds for the light to go out.

I always do the oil changes on the TB and my 2005 Tahoe Z71 5.3, at 4k miles or 4 month intervals, whichever comes first.

 

[AmpOverload]

IIRC, on the TB, the Change Engine Oil light is lit up when the engine is started, just like a CEL, and then goes out when engine is running and the you let go of the key. Before I did the slower 3 pedal push to floor trick, the Change Engine Oil, after the engine was running it would take 5-7 seconds for the light to go out.

I think I may have been unclear... I was speaking only about the KOEO pedal-pushing "reset" process itself and the expected flashing of the lamp almost immediately after that's been successfully done. Lamp activity at any time other than right after a successful "reset" process is a separate issue.

If that lamp doesn't start flashing within about 5 seconds after doing the reset procedure, regardless of whether or not it's on when you initiate the procedure, I'd be surprised. It's basically the GM way of showing that the reset worked, on a vehicle without the DIC but with a dedicated "CHANGE ENG OIL" (or similar) lamp. (On vehicles with the DIC, you can simply verify that the displayed oil life value jumps to 100%.)

 

[movietvet]

I think I may have been unclear... I was speaking only about the KOEO pedal-pushing "reset" process itself and the expected flashing of the lamp almost immediately after that's been successfully done. Lamp activity at any time other than right after a successful "reset" process is a separate issue.

If that lamp doesn't start flashing within about 5 seconds after doing the reset procedure, regardless of whether or not it's on when you initiate the procedure, I'd be surprised. It's basically the GM way of showing that the reset worked, on a vehicle without the DIC but with a dedicated "CHANGE ENG OIL" (or similar) lamp. (On vehicles with the DIC, you can simply verify that the displayed oil life value jumps to 100%.)

I just went out and checked. I can turn to KOEO and within 2 seconds I see the Change Engine Oil light and all the other cluster lights and they go out and then I start the engine and the same lights do the same thing and show then go out within 2 seconds.

The problem before was that after I had the dead battery problem, The lights did all do the same thing I just said, EXCEPT that the Change Engine Oil light would remain on for 7-8 seconds, instead of 2 seconds, and then go out, after the engine was started.

 

[AmpOverload]

I just went out and checked. I can turn to KOEO and within 2 seconds I see the Change Engine Oil light and all the other cluster lights and they go out and then I start the engine and the same lights do the same thing and show then go out within 2 seconds.

Forgive me, I don't mean to drag this out, but I think we're still on different pages.

You're talking about what the light does now, when you go to KOEO, without doing the pedal-pushing reset procedure.

I'm talking about what the light did (or would do, if you tried the "reset" again) right after you go KOEO and perform the pedal-pushing reset procedure. Maybe you didn't notice if it was flashing immediately after you did the reset that you mentioned in post #19, but I do suspect that it was flashing, unless maybe you changed the key position too quickly after those 3 pedal pushes.

FWIW, I'm convinced that you've successfully reset the engine oil life to 100%. I just wondered if the "CHANGE ENG OIL" light flashed right after you did the reset (i.e. ideally without ever having changed the key position).

 

[movietvet]

Forgive me, I don't mean to drag this out, but I think we're still on different pages.

You're talking about what the light does now, when you go to KOEO, without doing the pedal-pushing reset procedure.

I'm talking about what the light did (or would do, if you tried the "reset" again) right after you go KOEO and perform the pedal-pushing reset procedure. Maybe you didn't notice if it was flashing immediately after you did the reset that you mentioned in post #19, but I do suspect that it was flashing, unless maybe you changed the key position too quickly after those 3 pedal pushes.

FWIW, I'm convinced that you've successfully reset the engine oil life to 100%. I just wondered if the "CHANGE ENG OIL" light flashed right after you did the reset (i.e. ideally without ever having changed the key position).

Ok, I see what you are asking but I thought with my step by step story you would pick up on the fact that it never did do a "flash or flashing". I purposely did wait before and after each pedal pushing sequence, to see what the light would do. I wanted to know if it ever did anything other than what I expected it to do, which was shut off immediately after starting the engine, instead of what it was doing, which was the 7-8 second delay before turning off, after the engine started. I wasn't looking for or expecting a flashing sequence but NO it never did flash.

 

[movietvet]

Forgive me, I don't mean to drag this out, but I think we're still on different pages.

You're talking about what the light does now, when you go to KOEO, without doing the pedal-pushing reset procedure.

I'm talking about what the light did (or would do, if you tried the "reset" again) right after you go KOEO and perform the pedal-pushing reset procedure. Maybe you didn't notice if it was flashing immediately after you did the reset that you mentioned in post #19, but I do suspect that it was flashing, unless maybe you changed the key position too quickly after those 3 pedal pushes.

FWIW, I'm convinced that you've successfully reset the engine oil life to 100%. I just wondered if the "CHANGE ENG OIL" light flashed right after you did the reset (i.e. ideally without ever having changed the key position).

I am sorry for the confusion. Really, I am. I was in the shops for 45+ years and 35 of that as a service manager/advisor/writer and I was very detailed with my questions to customers. I am 73 now and sometimes I go down the wrong path when explaining. Typing answers and questions lose a bit of context, instead of talking. Again, sorry.

 

[AmpOverload]

I am sorry for the confusion. Really, I am. I was in the shops for 45+ years and 35 of that as a service manager/advisor/writer and I was very detailed with my questions to customers. I am 73 now and sometimes I go down the wrong path when explaining. Typing answers and questions lose a bit of context, instead of talking. Again, sorry.

No apology necessary, good sir! Indeed, I should both apologize for (and thank you for indulging) my (excessive!) curiosity.

I was just puzzled to hear about a GM vehicle without the DIC but with a dedicated "CHANGE OIL" lamp that didn't flash after an oil life reset.

I try to understand and correlate various vehicles' behavior well enough to be useful to folks (both on the Internet and in person), but GM's various inconsistencies continue to stymie my efforts!