U0100 Chevrolet -

Question

i touched the ac switch terminals with a hot wire from the + side of the battery ,it made the motor rev up an then it shut down ,now it wont crank over with the key ,an if i jump it at starter ,it will turn over but not fire ,the code u0100 came up ,i checked the fuses an the relays ,there all good an wen i turn key on to start ,the relay will click but wont turn over the starter . i was trying to jump the ac switch to see if the ac compressor was working ,i shouldnt had used a hot wire ,can any one help me .i hope i didnt burn the computer up .thank you

Answer 1

U0100 Loss communication with ECM

If you directed the started to start the engine you will set a U0100. What need to be trouble shoot is why it will not crank with the key. The worste the would of happen is a fuse developed a high resistance. The ECM is tougher than you can imagine.

What on the A/C circuit line are the CKP, Camshaft position sensor ,fuel tank pressure sensor, and other sensor  this is the reason it idle strangely. injecting a 12 volts to this, these sensor can handle it, Finding the reason it will not start with the igniton is where you need to solve the problem

 On the starter relay there is a fuse, disconnect it , check the circuit legs of the fuse , just looking at the crank fuse it also turns on certain components

 Here again is the crank fuse , if this Crank fuse is not function or its circuit not functional , , you would have no wiper action, and no start it gives power to the PWR/ TRN relay.