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Posted

 My brakes have been acting up at slow speeds, 2017 Silverado, 71k miles, 5.3 engine. I have a good code-reader, shows ‘Electronic Brake Control  Module’,  C0800-5A . I see the history with vacuum pumps, braking issues & brake controllers.

 

  I’m taking it to the dealer tomorrow afternoon for evaluation. I don’t want it to become more of a safety issue. I’m a mid-grade wrencher, maybe slightly below that. I’m looking for advice before I take it in. There may of been a recall already on this, none open now.

 

  There seems to be history with these braking issues, had similar on an older truck. Anything I should print off & take with me? Thanks. 

Posted

C0800 is a voltage/ground issue. Good chance it is a cable issue.

Posted

 I do think is a controller for the regular brakes, not a trailer brake controller. 
 

  I took a few scans, don’t know what ones had engine off with just ignition to run.

 

  The only other code was also under the same title of ‘EBCM’. That code is, U0073-00, says ‘control module communication bus A off’.

 

 I’ll put an update in once back from the dealership. 

Posted

 Back earlier from the dealership, very satisfied. The issue was a weak output from the vacuum pump, they put in a new pump & corresponding belt. This is an issue that has come up among many with a search.

 

  It took a full 1.5 hours, parts in stock. I haven’t had time for a code check yet, the brakes work perfectly at the slow speeds, engine at idle. That vacuum pump  looks a bit hard to get at.

 

  There was no cost to me. It’s kinda like an ‘on demand’ recall,  with no open recalls on this truck currently. 

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