ECM DTC 41 is a problem with circuit 423 a White wire from

ECM Gray connector pin 12 to the Ignition Control Module White wire Pin B.

DTC 41 can set if voltage is detected on circuit 423 when the ignition is on and the engine is not running or cranking.

Can also set if the voltage is greater than 4.6 volts and the engine speed is less than 1500 rpms. Normal voltage during cranking or running should be 4.5-.5 volts.

To eliminate the tach filter, poke its pin out of the Coil Gray connector Pin A or cut the wire and see if that cures the starting problem. The Tach signal is used by the dash cluster and also the Electronic Brake and Traction Control Module.

If the Mirror courtesy/map lamps work with the switch but not in the courtesy switch position. At the mirror you need to measure the voltage on the Orange wire shown as circuit 740. It gets 12 volts from the RH CTSY fuse which is hot all

the time. The ground on the White wire circuit 156 comes from the Courtesy Lamp Relay which closes when either door is opened.

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