DTC 45

Code 45 Chart:

Idle Switch Circuit Wiring Diagram:

CIRCUIT DESCRIPTION:

A Code 45 will set if the ECM senses the switch is closed, or circuit ground at off idle conditions.
The idle switch is used to signal the ECM when the throttle is in the closed or idle position. When properly adjusted, a closed throttle will pull the ECM circuit low (to ground) through the TPS idle switch. The idle switch, if measured separately, will show little or no resistance when closed. When the throttle is opened, the circuit will go high at the ECM and the switch, if measured separately, will show open or infinite resistance.

TEST DESCRIPTION: The numbers below refer to circled numbers on the diagnostic chart.

1. At Wide Open Throttle (WOT), the TPS idle switch should be open.

2. Checks for TPS harness shorted to ground at throttle body.

3. Checks for short to ground or circuits shorted together on ECM side of TPS connector.