Got my ABS codes read, need help

[MikeInCtown]

Can someone tell me what these two codes mean?

 

C0242 and C0246

 

It is a 2004 GMC Sierra 2wd

 

When I first got the truck the ABS light would go on only when it got really hot out and after a nice drive. As time went on, it happened anytime the weather was warm, then eventually even when it was cold, though the colder the weather, the longer the light takes to come on. I was hoping for a hub sensor diagnosis, but this appears that it could be in the ABS module under the frame. Would like you guy or someone who knows the codes to confirm.

[txab]

The codes mean you have an internal malfunction in your ABS unit. Their are places to get them rebuilt

[MikeInCtown]

This one of those deals where I undo the 4 torx screws from the top of the ABS unit and pull the top half off and send it away?

 

Had to do that with an ABS unit on a Jimmy once, but I knew that was the issue on that vehicle because the motor wouldn't turn off.

[efritz]

Before you send it away, be sure that it is rebuildable, beginning in 04, there was only one type used that is readily rebuildable.

[txab]

Before you send it away, be sure that it is rebuildable, beginning in 04, there was only one type used that is readily rebuildable.

+1

[MikeInCtown]

Not sure if you can tell but it is the JC3 braking system. I looked at the box when I was under the truck replacing my exhaust Saturday. Two harness connectors coming up from the bottom but I don't know if they are all like that. I know when I looked at the Module Masters web page they only list the one for my truck, but that might be the only one they rebuild, not the only one available on that model.

 

Edit: Oh great I looked up the modules on Rock Auto and they all list modules "except traction control" NW7 code, which is what I have. The only module they list with traction control is a $600 deal.

ACDELCO Part # 88983891 OES
MODULE,ELEK
BRK CONT 2 WHEEL DRIVE; w/7200# VAC PWR BRAKES(JC4) or TRACTION
CONTROL(NW7) or FOUR WHEEL STEERING(NYS); Engine VIN T

[efritz]

usually the one with two connectors is a Kelsey Hayes 325 which is rebuildable. Send it to Module Masters in Idaho. They do an awesome job.

[txab]

^^^

+1

 

You should have the 325, I do on my '04 Sierra

[Red Clay]

Depends on the top of the module. A 325 has a grey plastic like top the series 30 has a silver metal top. From what I have researched only the 325 is rebuildible. The 30 and 325 look the same from the bottom and have what look to be the same plugs.

[jblakeney]

Module Master

[nowicksl]

Resurrecting this thread.  I just replaced my module, rebuilt by Turnelectronics. I installed it, bought a scanner that allows me to not only clear the code, but to run the ABS module to open the valves to completely bleed the system.

 

I have the lights on the cluster, the ABS light and parking brake light. I can't clear the code, it won't clear, therefore I can't run the ABS module to bleed the system.  I have brake pressure, and can drive the truck but the ABS will not work, the rear tires will skid or all 4 will skid on the gravel.  Cleaned the ground etc.

 

Anyone know how to test that the wiring TO the module is good?  I can't think of anything else that may be wrong, but the Code C0246 cannot be erased as there is still a fault somewhere.

[nowicksl]

After Turnelectronics checking my module again (thank you Chris - awesome customer service) I have reinstalled it and still get the 0242 code.  Anyone here had to replace the ABS brake module or motor to clear this up?  I am now thinking that a valve is stuck due to corrosion or inactivity for many years?  Is this possible?