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So I have no experience using fault codes related to cars (i work on aircraft). I had one Key On Engine Off code: 512
and several Key On Engine Running codes: 173, 411, 412, 538
Looking for help as to what they mean and what I need to do!
Thanks for any help. I've had the truck for 8 months.
512 Keep Alive Memory Test Failure
This means that your ECU isn't receiving voltage on pin 1 and your computer is starting from scratch everytime it starts up. It could also be from someone disconnecting the battery recently or a internal computer failure, but check voltage on pin 1. It should have battery voltage at all times.
Code 512 is a Stored Code and as noted previously is typically caused by someone disconnecting the battery to clear the codes or other service work. You can clear it, do not disconnect the battery, then drive the truck for a few drive cycles and recheck.
Code 173: HEGO sensor circuit indicates system rich. An overly rich condition will kill a converter in a short time.
Code 411: Cannot control rpm during KOER low RPM check. Code 412: Cannot control rpm during KOER high RPM check. Does the truck have a high or low idle?
Code 538: Insufficient RPM change during KOER dynamic response test/ Operator error. Did you goose the throttle during the KOER tests?
Code 411/412: I believed it idled normally, generally between I wanna say 700-1000 RPM's?
Code 538: It is possible I did not doo a good enough "gooseing"
