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GMC Sierra – No Start, Is it 1983?

2020 GMC sierra

We’re continuing our streak of longer (truck-related) resource articles referenced, but this one is a bit less convoluted, makes for an easier read and ends with a good outcome and a happy customer. But, like the others, it just might save you some serious time and a lot of headaches. In it, Enrique from California recounts the tale of a difficult 2020 GMC Sierra where a customer asked him to program a new PCM “because of a code p0606.” 

Enrique installed the new PCM, completed the programming and relearns, but the vehicle wouldn’t start. He retraced his steps, even reinstalled the old PCM (which was driven in with the truck prior to the repair). Nothing. He performed a visual inspection to be sure he didn’t disrupt anything during the repair process, but found nothing amiss. He went back through the install and programming for the new PCM a second time, double checking every step. The truck still wouldn’t start. The only clue he found was a repeated odd noise when he push the START button. 

Here’s a hint from his story: “Before that I must say the customer had already turned the steering wheel all the way to the left to give me maximum access to the wheel well. this is a modified suspension with bigger tires so it was relatively easy to get to PCM without removing either the wheel or the liner.” I leave it there. Click the image or the link below to read the full story. It’s well worth it.

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