does anybody know what can cause both engine brakes not to work? ithey worked until i parked it for about 24 hours, and it stopped working after that/ i have gone through the entire harness, and 12 volts does get to the solenoid, but when i jump a negative wire straight from the battery to the solenoid i can hear it clicking. both the the EPG and compression braking stopped working. took it to the volvo dealership in town and they cant figure it out either, but according to the guys here the mechanics at the volvo are just street mechanics that dont know jack any ideas?
Knowing wheather or not the engine goes into warmhold would help diag. If it does, pretty certain the TPS is good. Are there ABS/TCS faults? With some codes from the WABCO system, the engine brake will not operate.
i will check codes when it comes back. i dont have any computer diagnostic tools also. so i either go off what the onboard computer says or just find the wiring problem (which is usually is, not always)
bought a new wiring harness and that fixed it. i found 2 or 3 shorted wires for the engine brake behind the plastic wiring casing. il probably just fix those and have a spare harness
