P1635

Diagnostic Chart:

Wiring Diagram:

Circuit Description

The PCM provides a 5 volt supply for use in powering up sensors. This test monitors the voltage present at terminals BRD13 (shared by Boost, EGR Control Pressure/Barometric pressure (BARO) and Crankshaft Position sensors) and BRD14 (Optical/Fuel temperature sensor (Cam/HI.Res).

Conditions for Setting the DTC

5 volt reference is less than 1 volt.

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

^ 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

During the time the failure is present, the setting of additional DTCs that share a 5 volt reference may also set.

Test Description

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

2. Checks to confirm that a DTC is still present.

3. Checks to determine if there is a 5 volt reference from the PCM.

4. Checks to determine if there is a short-to-ground in the reference circuit or a short-to-ground in the PCM.

7. This step determines if the short is being caused by one of the sensors on the engine or the short is in the wiring harness.