I'm getting a Code 12 and no other. The aftermarket Haynes repair manual I have lists it as "Battery power to PCM was disconnected". Does anyone know what this means? Does it mean that the PCM is not getting power/is disconnected from the battery? Or does it mean that I had previously disconnected the battery (whcih I did to clear it). But it obviously it didn't clear. Any thoughts appreciated.

I'm getting a Code 12 and no other. The aftermarket Haynes repair manual I have lists it as "Battery power to PCM was disconnected". Does anyone know what this means? Does it mean that the PCM is not getting power/is disconnected from the battery? Or does it mean that I had previously disconnected the battery (whcih I did to clear it). But it obviously it didn't clear. Any thoughts appreciated.




that means you have recently disconnected your battery. you should get a 12 and a 55 code. which means end of test.

Thanks teemsta. I had thought the code 12 would clear. Yes, I did also get the code 55 to indicate the end.