Not sure if anyone has heard of this problem. The TCS light will be on with no codes. You must use the bendix software to look at the configuration. More than likely the the ECU has lost its RSC Roll Stability Control programing.
You can go into the configuration and see if Yaw and RSC can be enabled. If you can't enable it only a Volvo dealer has the programing to reprogram the ABS ECU or replace it.
Bendix now has a RDU available for reprogramming the ABS ECU to take care of this problem. The RDU plugs into the 9 pin diagnostic connector with the ignition on the RDU will flash the ABS ECU. It only takes about 4 seconds to reprogram.
Yeah, I bought that RDU before I realized all my ABS systems are Meritor Wabco and that thing doesn't work with them at all. I have waged a war on my abs lights since I inherited a ton of trucks with codes.(my favorite finds were the WSS butt connector splices) Now all I have left are a few stubborn trucks with a code 7-3 that means "retarder fault",...OK no problem except none of the mixers have any form of retarder and I can't clear that code.
Keep in mind Bendix has several types of RDU's 1. Diagnostic RDU for tractor and trailer. 2. Programming RDU's for flashing ABS ECU's.
As for your 7-3 code the retarder can be for the engine brake. On older trucks that don't use the J1939 Data link to transmit the retarder signal from the ABS to the Engine ECU, used a signal wire to a retarder relay. I use to run into this problem alot on Freigthliners. The relay is a micro relay that has a row of 3 pins and a row of 2 pins. Some times the relay would be missing or reversed and the retarder signal was not connecting to the middle pin in the row of three. To sum it up.... The engine brake switch ground signal goes through the normally closed side of the relay to the engine ECU. When the ABS detects a wheel spin or ABS condition it sends a signal to the relay to open the signal from the engine brake switch and therefore the retarder or engine brake is disabled. If that ABS ECU does not detect the resistance of the relay it will give the code for retarder.
1. You have a proplem with the retarder signal or relay. 2. If it really does not have a retarder relay or input, the ABS ECU needs to be reconfigured.
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