P1635

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/BARO and crankshaft position sensors) and BRD14 (optical/fuel temperature sensor (cam/hires).

Conditions for Running the DTC
The ignition switch in the ON position.

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 is stored in the Failure Records.

Conditions for Clearing the MIL/DTC
^ A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures
^ The 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.