• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

Parking Brake Light On - NO ABS LIGHT!

HISZ66HERZ71

Full Member
Joined
Oct 30, 2019
Messages
12
Location
Springfield, Oregon
2003, Z66 1500 - I recently had the ABS module replaced, which took care of the ABS light on the dash.  But now I still have a Parking Brake warning light and the "Service Brake System" warning on the DIC.  Parking brake pedal and switch?  Brake fluid reservoir level sensor?  How would I check the level sensor with my DVM?  Or can it even be checked without simply replacing it?

Thanks in advance. :E:
HisZ66
 
Well... I found the problem causing the Parking Brake light to stay on, along with the Service Brake System message on the DIC...  I finally popped the hood to disconnect the battery for some other ignition and door panel work.  I looked under the brake fluid reservoir to check on the sensor...  It was missing.  Along with the connector and wiring harness for the sensor.  Does anyone know where this wiring harness and connector route back to so that I can try to see if mine is still intact?
Thanks In Advance
HisZ66
 
So... still looking into this problem.  Apparently not all trucks that have the reservoir with a place for the sensor had a sensor installed in that location.  Would anyone here know the different conditions that would set the Parking Brake light and the Service Brake System message on the DIC?  I'd like to get this truck to stop dinging at me incessantly after turning on the key!  :E:
Thank you,
HisZ66
 
Have you scanned for codes with a tool capable of reading ABS?
 
Have you figured out the issue with the parking brake light and the Service Brake System message on the DIC? I am having the same issue with mine and can't figure it out. I have an 03 z71. I just purchased the truck and had to replace the 4wd actuator. After replacing I get just a parking brake light and service brake system on my DIC. No ABS light and the brakes go almost all the way to the floor before engaging. I've read a lot of threads on here already and everything seems to point to the EBCM. Every thread I've read about the EBCM being bad people say their parking brake light and ABS light are both on. Can it be something else causing just one light to stay on and not the other? Checked brakes all around truck and they are solid. Checked and cleaned grounds. Checked wiring connector for EBCM. Codes I'm getting are just some EVAP codes and C0291. I apologize for making another post about brake problems on here. I just couldn't seem to find an answer as to where to go. Plan is just to send my EBCM and get it repaired unless anyone could tell me something else that it might be. Any advice would be much appreciated.
 
PCregal79, is your scan tool SRS capable (reads ABS codes?) Many of the home-use scan tools, like mine, can not read SRS.
 
PCregal79, is your scan tool SRS capable (reads ABS codes?) Many of the home-use scan tools, like mine, can not read SRS.

Good point.

I have two scanners that can read SRS (Supplemental Restraint System or airbag system) and ABS (Anti-lock Braking System) error codes.

I have others that can not.

Start by making sure your scanner of choice can read the required codes.
 
Mine (2003 Z66) had an issue which I fixed by resoldering the conectors on the ABS module. Now when powering up the brake light shows, but it goes off even when the parking brake is engaged? Also, I have an Airbag system warning. I replaced the front impact sensors but still showing error. My Scan tool does not read ABS nor SRS.

Ideas?

On a andom one, when its humid the seat heaters activate on their own. Also, i go by with weeks when the front speakers dont turn on (open the door and they work, shut the door and they die off). Thoughts?

Love my truck, custom ordered it back in 2003. Would like to fix that and keep it for a couple more decades.
 
The seat heaters on my 2004 EXT randomly came on by themselves.

Ended up being a burned out seat heater element pad causing the strange behavior.

Driversseatheaterback04.JPG

First was the driver's seat back heater pad.

A year later, it was the driver's seat bottom heater pad.

I replaced each with Dorman pads I bought off of Amazon.

Both have been working great for over 6 years now.

Using a scanner that could read SRS codes, I found the cause of the airbag error in my 2003 Z-66 to be a broken wire inside the plastic sheathing right as it went into one of the connectors under the passenger side front seat.

You could not see the break since it was inside the plastic sheathing.

I had to test the length of every suspect wire under the seat until I isolated the point of the break.

After finding the break in the wire, I was able to solder the wire onto the pin and reinsert it back into the connector.

No more airbag errors for almost a year now.

Using the same scanner I found that the main wiring connectors under both front seats on our 2012 Acadia were bad.

I located a TSB for that truck and made the correct repairs.

Over two years running on this repair.

Point being, troubleshooting airbag errors is best started using a capable scanner.

Otherwise, be prepared to have plenty of ammo for the parts cannon.

Best of luck with your repairs.

:) (y)
 
Kudos for the great reply! I have plugged and unplugged everything under the seats BUT have not checked each wire. Just ordered a new more capable scanner.

THANKS
 
I have collected several scanners over the years.

Some of the early ones are pretty limited, while the later ones are more capable.

The trick is to find one that meets you needs without spending a fortune.

I do not need to have one with capabilities of a dealer scanner, but one that will read and deal with codes of the systems I am most likely to try to troubleshoot and repair.

My two favorites at the moment are the BlueDriver Bluetooth Pro OBDII Scan Tool for iPhone & Android and the Autel AL619 hand held.

Both seem to read the codes I need to see and address.

Other members here have posted about their preferred choices, but ATM I do not have any outstanding codes that need attention.

I will explore those as the need arises.
 
I got me a Launch CReader 629. I plugged it in and it found:

Code: B0022 Driver Frontal Deployment Loop (Stage 1) Resistance Low

A quick search seems to point to the steering wheel wiring or plugs. Suggestions? My first thought is to remove the airbag module and clean all contacts.

Also B0041 Left Front Side Deployment Loop Open

Thoughts>\?
 
Get proper service book before messing with air bag stuff.
 
I have dealt with the similar open loop SRS codes on two different vehicles.

Both times, the problem was open wiring connections and once found, were fairly easy to fix.

The "Resistance Low" message is telling you that you have a open connection of some sort.

The computer looks for certain resistance values for all SRS components and low resistance tells the computer there is some sort of open connection where there should not be one.

One single fault in the SRS system and the entire system is totally disabled until the fault is found and repaired.

The first one for me was a factory defective wiring connector under both front seats of our 2012 GMC Acadia.

This problem had been the subject of a recall, but the dealer that supposedly fixed the problem did a sloppy, poor job.

I found the TSB online and I performed the fix correctly.

The second time was on my 2003 Avalanche.

The problem with that one ended up being a wire that was broken inside the wiring sheath right as a wire connected to one of the pins going into a wiring connector under the passenger seat.

It took a bit of troubleshooting and testing to find the actual break in the wire since the plastic sheathing was not disturbed.

I had to take the passenger seat out of the truck and unwrap and test every single wire along the entire length of each wire.

It was a very tedious task, to say the least.

I would rather have just found a wire that was sliced into two pieces than one that was internally broken, as you can imagine.

After locating the break, I was able to disassemble the connector and remove the pin and then solder the wire back onto the connector pin and reinsert the pin back into the connector housing.

No more airbag errors on either vehicle.
 
I have dealt with the similar open loop SRS codes on two different vehicles.

Both times, the problem was open wiring connections and once found, were fairly easy to fix.

The "Resistance Low" message is telling you that you have a open connection of some sort.

The computer looks for certain resistance values for all SRS components and low resistance tells the computer there is some sort of open connection where there should not be one.

One single fault in the SRS system and the entire system is totally disabled until the fault is found and repaired.

The first one for me was a factory defective wiring connector under both front seats of our 2012 GMC Acadia.

This problem had been the subject of a recall, but the dealer that supposedly fixed the problem did a sloppy, poor job.

I found the TSB online and I performed the fix correctly.

The second time was on my 2003 Avalanche.

The problem with that one ended up being a wire that was broken inside the wiring sheath right as a wire connected to one of the pins going into a wiring connector under the passenger seat.

It took a bit of troubleshooting and testing to find the actual break in the wire since the plastic sheathing was not disturbed.

I had to take the passenger seat out of the truck and unwrap and test every single wire along the entire length of each wire.

It was a very tedious task, to say the least.

I would rather have just found a wire that was sliced into two pieces than one that was internally broken, as you can imagine.

After locating the break, I was able to disassemble the connector and remove the pin and then solder the wire back onto the connector pin and reinsert the pin back into the connector housing.

No more airbag errors on either vehicle.
I really appreciate your perspective. I will go into the plugs and wiring under the seats. I have had several issues with wiring. One of them not fixed but solved by the dealership in an unorthodox way....

That one was the ever blowing Ignition E fuse. It happens when you move the drivers seat....... they couldnt find a problem so their solution was to replace the fuse with a 30 amp...... I got under there and found that the harness would pinch a wire when the seat was moved forward. Fixed but the problem returned, new theory being the ignition switch

Other one was an issue with the signals. found a very thin pink wire on the column broken off the plug. Fixed!

Steering wheel watch coil harness, replaced.

I want to keep the truck but if I cant fix the AirBag system it might be time to let it go. Time to break out the ohmmeter and the box cutter.

THANKS!
 
Back
Top