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Home >> Ford >> 2022 >> F-150 Tremor >> Repair and Diagnosis >> External Pages >> Different car >> Section 601 (Electronic Engine Controls - 3.0L Power Stroke Diesel) >> Diagnosis And Testing >> Powertrain Control Module (PCM) Input and Output Controls >> Pinpoint Tests >> Pinpoint Test AJ: Powertrain Control Module (Pcm) Power Relay
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Pinpoint Test AJ: Powertrain Control Module (Pcm) Power Relay

WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Regeneration may occur during normal operation. During regeneration, diagnostic procedures may display biased values. If a regeneration occurs during diagnostic procedures, allow the process to complete before continuing diagnostics.

Normal Operation and Fault Conditions 

Refer to the DTC Fault Trigger Conditions.

DTC Fault Trigger Conditions 

DTC Description Fault Trigger Condition
PCM P0685:00 ECM/PCM Power Relay Control Circuit/Open: No Sub Type Information Sets when the PCM detects the ignition switch position run (ISP-R) circuit indicates the ignition is in the off or accessory mode, and the amount of time the PCM remains powered through the PCM power relay exceeds a predetermined amount of time.
PCM P068A:00 ECM/PCM Power Relay De-Energized - Too Early: No Sub Type Information Sets when the PCM detects the PCM power relay is de-energized too early.
PCM P068B:00 ECM/PCM Power Relay De-Energized - Too Late: No Sub Type Information Sets when the PCM detects the PCM power relay takes longer than a specified time threshold to de-energize after it was commanded off.
PCM P2507:00 ECM / PCM Power Input Signal Low: No Sub Type Information Sets when the PCM detects the PCM 5 volt power supply voltage is less than a calibrated threshold.
PCM P2508:00 ECM / PCM Power Input Signal High: No Sub Type Information Sets when the PCM detects the PCM internal 5 volt power supply voltage is greater than a calibrated threshold.

Possible Sources 

PINPOINT TESTS AJ: POWERTRAIN CONTROL MODULE (PCM) POWER RELAY (Diesel)