ABS ASR light
Thread Starter
2nd Gear
Joined: Jul 2025
Posts: 2
Likes: 0
ABS ASR light
I have a 1992 6sp, LT1, 35,000 mi. If down shift to take advantage of engine braking and get any wheelspin (rear tires rotating slower than front tires) it triggers the SERVICE ABS and ASR warning lights and they on until I shut off the car, when I restart it the SERVICE ABS and ASR lights are out. If the ASR is triggered while accelerating it functions properly with no warning lights. Any one have any ideas on what's causing this?
Race Director
Joined: Oct 2012
Posts: 17,386
Likes: 6,529
From: Melbourne, FL
First of all, that's some really terrible driving. Brake pads are way cheaper than motors, engine braking is not your friend. Second, you shouldn't be getting wheelspin from downshifting, something very, very wrong is happening in your driving.
That all said, pull the codes from the CCM, possibley immediately next time it happens. If you want to try to solve it now, check your brake fluid level. If your fluid is a little low, you could be tripping the brake fluid sensor and getting the lights.
That all said, pull the codes from the CCM, possibley immediately next time it happens. If you want to try to solve it now, check your brake fluid level. If your fluid is a little low, you could be tripping the brake fluid sensor and getting the lights.
Melting Slicks
Joined: Nov 2016
Posts: 2,256
Likes: 3,083
From: So Cal
2023 C4 of the Year Finalist - Unmodified
FAUEE: That all said, pull the codes from the CCM, possibley immediately next time it happens.
Excellent suggestion. The H codes will remain in CCM memory for 50 Ignition cycles, then self-clear. Unless the fault occurs again. You don't have to pull them right away.
If your fluid is a little low, you could be tripping the brake fluid sensor and getting the lights.
Again, excellent suggestion. And thinking.
The first time I had the lights come on for Low Brake Fluid in my 92, I also got the red BRAKE light in the Halo. 3 Lights all at once! It startled the **** out of me, and also elicited a "What The **** can cause all this at the same time? All I did was get on it a little hard on a green light." Pulled the codes, there were 2 Low Brake Fluid codes, and that's what it was. Cheers.
Excellent suggestion. The H codes will remain in CCM memory for 50 Ignition cycles, then self-clear. Unless the fault occurs again. You don't have to pull them right away.
If your fluid is a little low, you could be tripping the brake fluid sensor and getting the lights.
Again, excellent suggestion. And thinking.
The first time I had the lights come on for Low Brake Fluid in my 92, I also got the red BRAKE light in the Halo. 3 Lights all at once! It startled the **** out of me, and also elicited a "What The **** can cause all this at the same time? All I did was get on it a little hard on a green light." Pulled the codes, there were 2 Low Brake Fluid codes, and that's what it was. Cheers.
Thread Starter
2nd Gear
Joined: Jul 2025
Posts: 2
Likes: 0
First of all, that's some really terrible driving. Brake pads are way cheaper than motors, engine braking is not your friend. Second, you shouldn't be getting wheelspin from downshifting, something very, very wrong is happening in your driving.
That all said, pull the codes from the CCM, possibley immediately next time it happens. If you want to try to solve it now, check your brake fluid level. If your fluid is a little low, you could be tripping the brake fluid sensor and getting the lights.
That all said, pull the codes from the CCM, possibley immediately next time it happens. If you want to try to solve it now, check your brake fluid level. If your fluid is a little low, you could be tripping the brake fluid sensor and getting the lights.
I've owned the car for 6 years. I had the car out on Sunday. A passing rain shower dumped an inch of rain on on a stretch of road 5 miles from my house. (Not an uncommon occurrence here in FL). I was approaching a right turn and was braking and used heel toe to bring the revs up for the downshift (I learned how to heel toe when I autocrossed in NCCC events back in the 90s) I missed judged the revs by a few hundred rpm too low and when I downshifted the rear wheels lost traction for 1/2 second. I know I'm am a terrible driver for letting this happen. Should I drive my Corvette like my grandmother drive her Prius?
I pulled the codes and none were found. Car has 35,000 miles on it.
Melting Slicks
Joined: Nov 2016
Posts: 2,256
Likes: 3,083
From: So Cal
2023 C4 of the Year Finalist - Unmodified
Did you use the onboard diagnostics? (I recognize that you've owed the car for 6 years. Have you learned how to use the onboard diagnostics where the fuel and odometer buttons are used to display codes for the CCM, Engine, ABS, and TCS in the speedometer LCD?) Jumping A&B and watching the Service Engine Soon light will not reveal ABS/TCS codes.
If those two lights came on, there should be a stored code(s) in Module 9. Low Brake Fluid is a Module 9, H83.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~
The ABS/TCS systems both utilize the same module which controls the Brake Pressure Modulator Valve for both functions. Because you were braking (foot on the pedal) the system was in ABS mode. The down-shift wheel-skid initiated an ABS intervention where a fault in the BPMV was then detected. From my experiences with my 92, Many ABS/TCS fault codes turn on both SERVICE ABS and TCS lights. It may not be low brake fluid, but If a light comes on, a code was set which can be retrieved with the onboard diagnostic.
If you need guidance for using the onboard diagnostics, ask.
If those two lights came on, there should be a stored code(s) in Module 9. Low Brake Fluid is a Module 9, H83.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~
The ABS/TCS systems both utilize the same module which controls the Brake Pressure Modulator Valve for both functions. Because you were braking (foot on the pedal) the system was in ABS mode. The down-shift wheel-skid initiated an ABS intervention where a fault in the BPMV was then detected. From my experiences with my 92, Many ABS/TCS fault codes turn on both SERVICE ABS and TCS lights. It may not be low brake fluid, but If a light comes on, a code was set which can be retrieved with the onboard diagnostic.
If you need guidance for using the onboard diagnostics, ask.
Last edited by IHBD; Jul 28, 2025 at 01:53 PM.
