Medium and Heavy Trucks
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Hi my name is***** you still need help with this? and if so are you getting any fault codes?
thanks for the update. Check if the check engine light is coming on and cycling with the key on as it should. If not check the inline fuse and wiring between the battery box and ECM for corrosion or poor connections. If okay and the check engine light comes on or stays on with the engine running it means you have an active fault code. This code will point to the circuit that has a problem requiring testing. Try to pull your codes with the flash code procedure. Key on with cruise off, hold the set/resume switch or diagnostic switch until the check engine light begins to flash. Count the flashes for the two digit code with a short pause in between each digit and a longer pause in between each code. This will repeat until the key switch is turned off. Let me know if successful in getting the codes this way and what you get for codes.
Or you need a heavy truck scan tool to pull the codes. Cat uses Cat ET software but some generic truck scan tools will read the codes.