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No ABS or Brake Light on Dash

stevedenali

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stevedenali Enthusiast

stevedenali

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Posted

Hi, 

I have a 2005 Sierra Denali. When I got the truck from my uncle who was the original owner, the gauge cluster, which was brand new installed by GM did not illuminate the ABS and BRAKE lights. Everything else works. I pulled the cluster apart and tested that those LED’s work, and they do. I replaced the ABS pump unit because it was not functioning, and had the EBCM rebuilt. The ABS functions correctly now with the exception of those lights that have never been on since I got the truck. Even if I press the Parking brake/E-brake, the red BRAKE light stays off but it will ding at me if try to drive with it on, similarly, before I replaced the ABS pump, I got a message in the odometer screen saying “Service Brake System”, no lights from either. No fault codes. They don’t even come on when cycling the key, but all the other ones do. I’m at a loss. Can’t find any broken wires or bad grounds.  Any help would be great. Thank you!

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