Q: Getting a p138b code - should I just replace the GPCM? I think a nearby lightning strike may be the culprit.

asked by on January 12, 2017

Getting a p138b code - should I just replace the GPCM? I think a nearby lightning strike may be the culprit. Is the GPCM fairly easy to access? I've not looked for the GPCM under the hood yet.

My car has 162000 miles.
My car has an automatic transmission.

Hi there. If the codes for the engine are coming up with the glow plug control module failure, then check the module to see if there is any wiring burned or broken. If there is nothing wrong with the harness or the wiring to the module, then I recommend replacing the glow plug control module. The glow plug control module is located on top of the engine with a black plug and a green plug attached to it. If you need further assistance with replacing the glow plug control module (timer), then seek out a professional, such as one from Your Mechanic, to help you.

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