Abs light error code 77/ Help!
08-01-2018, 01:01 PM
#16
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08-01-2018, 01:05 PM
#17
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Re: Abs light error code 77/ Help!
i inspected the wiring by hand looking for any soft or hard spots. when i pointed the harness down i noticed a little water came out of the covering. when i cut the covering back i found a spot that had a little muck. when i cleaned that off the wires seemed a little soft there and a little fat a little further up. after i replaced the harness i cut the old one open and found the wires started to rot in one spot and in the fat spot the wires were oxidized . at first it would only happen in the winter on cold days or highway drives. im assuming the water that was trapped in the covering would freeze preventing communication with the hub. i deleted the abs in my 95 so i have parts if you need -- -al
08-02-2018, 04:01 PM
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Re: Abs light error code 77/ Help!
Just for clarification, Do I check the resistance on the EBCM connector from the ABS pump or disconnect the EBCM connector from the EBCM module that is located underneath the driver side panel and check resistance there? Sorry but I am not incline in electrical diagrams nor electronic language or terms. It’s all foreign to me. I use google to break down the language for me and for interpretation. The service manual seems not very clear on this or it could just be me.
The diagram on Page 5E1-28 will help you identify pin "B1" in the 32-pin connector.
Then check the dark green wire from the EBCM to the front/left solenoid for damage. Check for loose or damaged pins in the 32-pin connector to the EBCM, and for the 2-pin connector at the left/front solenoid.
Last edited by Injuneer; 08-02-2018 at 04:07 PM.
08-12-2018, 06:57 PM
#19
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Re: Abs light error code 77/ Help!
There is a 32-pin connector at the EBCM (above driver's side kick panel). Unplug that connector. Set your meter to "ohms". Connect one lead to pin "B1" in the harness connector. Connect the other lead to a good chassis ground. The meter should read "out of range", meaning the resistance is "infinite". That would mean there is no "short to ground" on the dark green wire that runs from pin "B1" in the EBCM harness connector to pin "A" on the left/front ABS solenoid connector.
The diagram on Page 5E1-28 will help you identify pin "B1" in the 32-pin connector.
Then check the dark green wire from the EBCM to the front/left solenoid for damage. Check for loose or damaged pins in the 32-pin connector to the EBCM, and for the 2-pin connector at the left/front solenoid.
The diagram on Page 5E1-28 will help you identify pin "B1" in the 32-pin connector.
Then check the dark green wire from the EBCM to the front/left solenoid for damage. Check for loose or damaged pins in the 32-pin connector to the EBCM, and for the 2-pin connector at the left/front solenoid.
Also, I switched the fuction on my multimeter to make a beep sound when continuity is detected. So I connected one lead to ground and the other to terminal b1 and my multimeter beeps, indicating there is continuity. Is this the same method to measure for resistance? Otherwise I may have a short somwhere in the dark green wire. I could not find anything obvious where the dark green wire may be damaged.
I’m stuck at this point so I’m just goIng to take it to a reputable mechanic and hopefully he can fix it. Injuneer, thanks for your help thus far!
08-12-2018, 07:54 PM
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Re: Abs light error code 77/ Help!
What scale was the meter on when you got a reading of 3.8-4.0?
If you have continuity, and are getting a resistance of less than infinity, it would appear you have a short to ground. But it would be helpful to know the exact units measured, assuming you had the meter on the ohms scale. DTC 77 sets when there is a short to ground. You have to find out where the dark green wire from pin B1 to the left ABS solenoid (circuit 1288) is shorted to another wire, or to the chassis.
If you have continuity, and are getting a resistance of less than infinity, it would appear you have a short to ground. But it would be helpful to know the exact units measured, assuming you had the meter on the ohms scale. DTC 77 sets when there is a short to ground. You have to find out where the dark green wire from pin B1 to the left ABS solenoid (circuit 1288) is shorted to another wire, or to the chassis.
08-12-2018, 08:21 PM
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Re: Abs light error code 77/ Help!
What scale was the meter on when you got a reading of 3.8-4.0?
If you have continuity, and are getting a resistance of less than infinity, it would appear you have a short to ground. But it would be helpful to know the exact units measured, assuming you had the meter on the ohms scale. DTC 77 sets when there is a short to ground. You have to find out where the dark green wire from pin B1 to the left ABS solenoid (circuit 1288) is shorted to another wire, or to the chassis.
If you have continuity, and are getting a resistance of less than infinity, it would appear you have a short to ground. But it would be helpful to know the exact units measured, assuming you had the meter on the ohms scale. DTC 77 sets when there is a short to ground. You have to find out where the dark green wire from pin B1 to the left ABS solenoid (circuit 1288) is shorted to another wire, or to the chassis.
Thanks
08-12-2018, 08:33 PM
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Re: Abs light error code 77/ Help!
But a meter usually has multiple scales, unless it’s auto-ranging. Scale could have been 1X, 100X, 1000X, etc. 3.8 on a 1000X scale would be 3,800 ohms.
3.8 ohms would be a very obvious short. 3,800 ohms might be harder to find.
3.8 ohms would be a very obvious short. 3,800 ohms might be harder to find.
10-06-2018, 10:30 PM
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Re: Abs light error code 77/ Help!
Update!! After so many long days trying to figure this issue out, I decided to buy another ECBM. Luckily while traveling for work I came across a totaled 1995 camaro z28 in small rural town in Colorado; sitting on the top of a trailer with doors missing and t-tops. The car looked it’s been sitting there for a few weeks. I took a gamble and stop by and asked for the owner. The owner said he was reared ended and the car had 90k miles.
Longstory short, I took the ECBM and the Airbag DERM module. I was not quit sure the ECBM would work on my Camaro since the service number did not match up with my original ECBM. I still took it and hope that it would work. I was so annoxious that day that I installed it the same day along with Airbag DERM module. And lo and behold all my lights are off. My dash doesn’t look like a Christmas tree anymore.
Thanks everyone for you help and chiming in!
Longstory short, I took the ECBM and the Airbag DERM module. I was not quit sure the ECBM would work on my Camaro since the service number did not match up with my original ECBM. I still took it and hope that it would work. I was so annoxious that day that I installed it the same day along with Airbag DERM module. And lo and behold all my lights are off. My dash doesn’t look like a Christmas tree anymore.
Thanks everyone for you help and chiming in!
10-06-2018, 11:45 PM
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Re: Abs light error code 77/ Help!
Thanks for closing this one out. Wish everyone would do that. It seems to validate step 4 in the DTC 77 troubleshooting chart - “Replace EBCM”.
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