Odd ABS Light, service brake system message - Page 3

crabtruck · 02-12-2009, 05:29 PM

Never rains, it pours ? Could be a different code / problem at this point ?
Could be dirty/bad wheel sensors. Get the codes read again, and after you think
you have cleared them, check to be sure.

Some thread here has the cleaning and testing proceedure for wheels,
look for it, it's pretty simple and straight foward, most it requires is small AC meter.

Someone posted above about getting a code reader instead of a scanner,
big difference in price and can get you pretty far. Mine cost $90 at kragens.

Ninja_Lawn_Guy · 02-14-2009, 08:13 AM

Ok, well the codes are the same but I have 2 questions: 1. If they are still "stored" in the comp, would they have a tendancy to pop back up if not cleared and 2. why would it only seem to do it when the truck is cold..?

0nly reason I say that is when I started it last night it was cold and it came on, but I drove for about 5 mins, turned it off at a light and it went away.

Same thing happened yesterday morning.

crabtruck · 02-14-2009, 03:52 PM

First make sure the ground for the EBCM is clean and tight,
usually that's on the frame beneath the drivers door and is a #12 wire.
There was a recall for the years right up to 2003, which was the year
they changed the ABS to not activate below I think 15mph.

The thing about codes showing up when cold temp or truck has me thinking.
If the warm truck is one that has been driven to get warm, the brakes are being
used generating heat locally. If the weather is warm the wheels will be warm.
Wheel sensors and the sensing rings are at a fairly close distance and heat will
slightly change that, maybe one has been banged during brake work ?
Those wheel sensors are subject to problems when dirty also, worth checking.

Temp change can also effect any connection or damaged wire. I know you already looked
at wires before but really give them the once over, and check plugs on tight.

Think that 291 BCM code is used generically for when there's no communication
meaning something may actually be coming unplugged. Since the light went away
I'm thinking this was that code and not the ABS ones. That's why I say to recheck
codes because you may not be getting the same ones back.
IE: all check eng lites look alike to me, need codes.

I'll try to see if anything jumps out at me when looking at wiring diagrams,
maybe I'll have more guesses without warantees

Ninja_Lawn_Guy · 02-14-2009, 04:33 PM

Ok will do...It's just weird is all..I guess anything is possible. I could have missed a loose plug or a cracked wire. I'll take some time on the wheel sensors too seeing as that was one of the first thoughts. Just when it went off and stayed off I thought I was in the clear.

Also the red service barke system light stayed gone too so I kinda figured it was an abs problem not full system problem.

It was screaming

ABS !BRAKE! SERVICE BRAKE SYSTEM back when I started this thread..

Ninja_Lawn_Guy · 02-15-2009, 12:37 PM

This plug aka sensor front is a little dirty but everything is tight and relitively clean looking...I disconnected and reconnected everyplug, checked every wire, checked fuses, F-ING NOTHING...I still have to take apart the front assemblies but it's not looking promising. Today, it just won't shut off..I thought about the warming it up thing, and that too did not matter

crabtruck · 02-15-2009, 01:07 PM

I'm forgetting exactly how to check those while installed. Seem to remember you could lift the wheel off the ground and spin it by hand. While it spins it would put out a small AC voltage. There's a thread about it here somewhere...

Ninja_Lawn_Guy · 02-15-2009, 02:36 PM

Ok I'll try to find it, but can I clean them while they're on? Or do I have to disassemble the whole deal? Also, there is one for the back 2 as well right?...where is that one?

And just as an added WTF....the check engine light that came on when I got the straight pipes shut off when I checked all the brake connections...still off even though it was for exhaust. Crazy shorts in my system,,,crazy system in my shorts HAHA

mudseeker · 02-15-2009, 06:24 PM

as far as i know those sensors on the hub are a sealed unit and can not be cleaned. the whole hub needs to be replaced if they are bad.

your problem has to do with the ABS pump, not any sensors.

crabtruck · 02-16-2009, 12:35 AM

May not be the ABS causing light anymore, think he needs to recheck codes.

Ninja_Lawn_Guy · 02-17-2009, 08:52 AM

Quote:

Originally Posted by crabtruck

May not be the ABS causing light anymore, think he needs to recheck codes.

3 messages ago I said I did...same codes..68 69 91

And the ABS light is the only one on...I'm looking into a pump just in case, and since mudseeker thinks so....that's my issue.

02-15-2009, 06:24 PM	#28
mudseeker Senior Moderator Join Date: Feb 2006 Location: michigan Posts: 6,373	as far as i know those sensors on the hub are a sealed unit and can not be cleaned. the whole hub needs to be replaced if they are bad. your problem has to do with the ABS pump, not any sensors. __________________ i'd rather be hunting

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02-12-2009, 05:29 PM	#21
crabtruck Senior Member Join Date: Jul 2007 Location: on your 9 Posts: 3,364	Never rains, it pours ? Could be a different code / problem at this point ? Could be dirty/bad wheel sensors. Get the codes read again, and after you think you have cleared them, check to be sure. Some thread here has the cleaning and testing proceedure for wheels, look for it, it's pretty simple and straight foward, most it requires is small AC meter. Someone posted above about getting a code reader instead of a scanner, big difference in price and can get you pretty far. Mine cost $90 at kragens.

02-14-2009, 08:13 AM	#22
Ninja_Lawn_Guy Senior Member Join Date: May 2008 Location: Michigan Posts: 412	Ok, well the codes are the same but I have 2 questions: 1. If they are still "stored" in the comp, would they have a tendancy to pop back up if not cleared and 2. why would it only seem to do it when the truck is cold..? 0nly reason I say that is when I started it last night it was cold and it came on, but I drove for about 5 mins, turned it off at a light and it went away. Same thing happened yesterday morning.

02-14-2009, 03:52 PM	#23
crabtruck Senior Member Join Date: Jul 2007 Location: on your 9 Posts: 3,364	First make sure the ground for the EBCM is clean and tight, usually that's on the frame beneath the drivers door and is a #12 wire. There was a recall for the years right up to 2003, which was the year they changed the ABS to not activate below I think 15mph. The thing about codes showing up when cold temp or truck has me thinking. If the warm truck is one that has been driven to get warm, the brakes are being used generating heat locally. If the weather is warm the wheels will be warm. Wheel sensors and the sensing rings are at a fairly close distance and heat will slightly change that, maybe one has been banged during brake work ? Those wheel sensors are subject to problems when dirty also, worth checking. Temp change can also effect any connection or damaged wire. I know you already looked at wires before but really give them the once over, and check plugs on tight. Think that 291 BCM code is used generically for when there's no communication meaning something may actually be coming unplugged. Since the light went away I'm thinking this was that code and not the ABS ones. That's why I say to recheck codes because you may not be getting the same ones back. IE: all check eng lites look alike to me, need codes. I'll try to see if anything jumps out at me when looking at wiring diagrams, maybe I'll have more guesses without warantees

02-14-2009, 04:33 PM	#24
Ninja_Lawn_Guy Senior Member Join Date: May 2008 Location: Michigan Posts: 412	Ok will do...It's just weird is all..I guess anything is possible. I could have missed a loose plug or a cracked wire. I'll take some time on the wheel sensors too seeing as that was one of the first thoughts. Just when it went off and stayed off I thought I was in the clear. Also the red service barke system light stayed gone too so I kinda figured it was an abs problem not full system problem. It was screaming ABS !BRAKE! SERVICE BRAKE SYSTEM back when I started this thread..

02-15-2009, 12:37 PM	#25
Ninja_Lawn_Guy Senior Member Join Date: May 2008 Location: Michigan Posts: 412	This plug aka sensor front is a little dirty but everything is tight and relitively clean looking...I disconnected and reconnected everyplug, checked every wire, checked fuses, F-ING NOTHING...I still have to take apart the front assemblies but it's not looking promising. Today, it just won't shut off..I thought about the warming it up thing, and that too did not matter

02-15-2009, 01:07 PM	#26
crabtruck Senior Member Join Date: Jul 2007 Location: on your 9 Posts: 3,364	I'm forgetting exactly how to check those while installed. Seem to remember you could lift the wheel off the ground and spin it by hand. While it spins it would put out a small AC voltage. There's a thread about it here somewhere...

02-15-2009, 02:36 PM	#27
Ninja_Lawn_Guy Senior Member Join Date: May 2008 Location: Michigan Posts: 412	Ok I'll try to find it, but can I clean them while they're on? Or do I have to disassemble the whole deal? Also, there is one for the back 2 as well right?...where is that one? And just as an added WTF....the check engine light that came on when I got the straight pipes shut off when I checked all the brake connections...still off even though it was for exhaust. Crazy shorts in my system,,,crazy system in my shorts HAHA

02-16-2009, 12:35 AM	#29
crabtruck Senior Member Join Date: Jul 2007 Location: on your 9 Posts: 3,364	May not be the ABS causing light anymore, think he needs to recheck codes.