I have a 2001 Astro with aprox. 148000 mi, and both the ABS and Brake lights on the dash have been going on and off intermittently for several weeks now. I have checked the fluid and it is full. It's dark and needs to be flushed, but, it is full. I have also removed both front wheels and have cleaned the sensors with brake cleaner and contact cleaner as well as removing them and scraping the mounting plate to ensure a good contact. This van is rear wheel drive and has disc in the front and drums in the back. I don't see any sensors on the back so I assume that sensors only go on the disc brakes. I have unplugged all of the connectors at the ABS module and cleaned them with contact cleaner as well. Whenever I disconnect the battery for any of this work, the lights stay off for as long as several days and then they come back on. I have had a mechanic scan it and he says that the EBCM is going bad. He didn't write down or remember the codes so I can't look them up. Is there anything that I have missed? I can't find where the sensors plug in to check those connections. I have gotten so many different opinions and answers that I'm not sure where to turn next.
The ebcm is electronic brake control module and is ontop of the abs module there really is nothing to clean if its bad its bad and needs to be replaced, also the rear should have abs but its in the diff and works off a reluctor ring for speed signal, look at the diff for a connector, check around for prices on the ebcm before you buy one, and check that against a gm reman online at gmpartsdirect. Com
October, 30, 2007 AT 5:11 PM
I would check out the sensors could be a output problem and check for resistance a small differance can cause a problem or fractured wiring on leads cheapist way
October, 30, 2007 AT 10:15 PM
Thanks for your ideas. I can't seem to locate the sensor that is at the differential. I'm going to go back under the car again and see if I can find it. I am also having a hard time locating the connectors for these sensors so I can put my DVM on them to measure the output voltage. Any assistance on where they are located is appreciated.
November, 8, 2007 AT 4:53 PM
Fred, I have exactly the same van & exactly the same problem. I authorized service center has just told me that the EBCM has to be replaced. It does not get fixed. It started with me after I went to have my motor cleaned. The guy started flushing water & I immediately stopped him & left, but seems it was too late. The ABS & the Break lights have gone on & remained for sometime, so I parked the car till the next day as it might have gone dry. The next day & maybe the day after aswell, the lights did not go on, but then afterwards it started to come on every 2-3 days & sometimes it did not come on for 2-3 days aswell. The service center did not give me the P/N but I think on ACDELCO it is 88982310 & it is called ABS Control Module which is sold @ $457 on gmpartsdirect. Com. If you reach a different solution please post it.
November, 11, 2007 AT 11:03 PM
I have found a service that I can ship it to in Massachusetts and they'll rebuild it for 99.00 plus shipping. Seems there is a switch that goes bad inside the EBCM. I have gotten the code C0265 which refers to an internal relay in the unit itself. I'm at the end of my rope so I'm going to give this one a try. I like this idea because if it does work, it already matches my computer and I don't have to have it reprogrammed. If I buy a new one, I have to pay someone an hour labor to reprogram it. I'll post if it works. If not, I'm out about 130.00 and still at square one.
December, 19, 2007 AT 10:43 PM
Sorry I haven't posted in a while. I haven't sent the part out (holidays, college tuition and all that good stuff). I'll be sending after the first of the year and I'll post the results then.
Have a good holiday!
April, 4, 2008 AT 1:10 PM
Fred. I have a 2001 AWD with 150000kms and the same problem. Lights come on after driving for 10 min. Or so. Sometimes after a bump and sometimes not. Scan shows that a relay is at fault. Tried to contact the guy who does exchange modules but no reply. Just came back from the dealer with the cost of the part at trade--$800. List $1100. Yipes. Dealer says they sell very few, but there is one in the warehouse. This is in Vancouver BC.
Does this thing affect the AWD function?
April, 11, 2008 AT 8:14 AM
Fred, have you sent it out to the guy in Massachusetts?
Has it been fixed?
Pls update us.
February, 6, 2009 AT 12:56 AM
I have got a refurbished module from ModuleMaster back in May 2008, installed it in the service center, & Thank God it is working fine. They also paid $60 rebate when I sent them the defected module.
Just wanted to let you know have you not reached a solution yet.