HELP!!HELP!! what does control-unit supply B+ mean? what are the things that we need to check out? we have checked on the battery supply, ground calbes of the engine to body, harness to body, alternator, starter, and harness. what else can we check? this error came out bec we did an engine swap from a 4 cyl to a 3L engine. everything came with it when it was purchased.

any advice?

I'm assuming that when you cancel the fault it returns. I'd start by checking voltage and ground at the control module connector. Pay particular attention to voltage from the main relay. Do not disconnect or connect the module with the ignition on.

This will show up every time you disconnect you battery for an extended amount of time. At least it did for me when I swapped to a 3.2 Clear the code and see if it comes back before you jump the gun on anything. If it comes back then I would worry and start checking the other mentioned parts.

HansundFranz: what should the voltage and ground at the control module connector and voltage at the relay be? i did not disconnect the dme while the ignition is on. if this is done what could happen - just out of curiosity.

PorjectE36:i have cleared the code so many times. it goes away but when everything is ok and start it it comes back again. the ews error would come out also. when we would align it with a gt1 the control-unit error still come on.

hope to hear from you guys

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