P1654

Diagnostic Chart:

Wiring Diagram:

Circuit Description

A dash light is illuminated by the PCM if the diagnostics has detected certain errors related to the Accelerator Pedal Position (APP) sensor. When the PCM is commanding the Service Throttle Soon Lamp ON, the voltage potential of the circuit will be low (near 0 volts). When the PCM is commanding the Service Throttle Soon Lamp OFF, the voltage potential of the circuit will be high (near battery volts). The primary function of the PCM in this circuit is to supply the ground for the Service Throttle Soon Lamp.


Conditions for Setting the DTC

^ Service Throttle Soon lamp requested ON.

^ Voltage on the Service Throttle Soon control circuit high (near battery volts).

or

^ Service Throttle Soon lamp requested OFF.

^ Voltage on the Service Throttle Soon control circuit low (near 0 volts).


Action Taken When the DTC Sets

^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).

^ The PCM records the operating conditions at the time the diagnostic fails. This information stores in the Failure Records.

Conditions for Clearing the MIL/DTC

^ The PCM will turn the MIL off after three consecutive trips without a fault condition.

^ A History DTC will clear when forty consecutive warm-up cycles that the diagnostic does not fail (coolant temperature has risen 5°C (40°F) from start up coolant temperature and engine coolant temperature exceeds 71°C (160°F) that same ignition cycle.

^ Use of a Scan Tool


Diagnostic Aids

A malfunctioning bulb or the control circuit shorted to ground will cause a P1654 to set.


Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

2. Be sure that both the ON and the OFF states are commanded. Repeat the commands as many times as necessary.

9. If no trouble is found in the control circuit or the connections at the PCM, the PCM maybe malfunctioning, however, this is an extremely unlikely failure.