FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0891











SYMPTOM
P0891 - TRANSMISSION RELAY ALWAYS ON

WHEN MONITORED
When ignition key is turned from the OFF position to the RUN position and/or ignition is turned from the CRANK position to RUN position.

SET CONDITION
This DTC is set if the Transmission Control Module senses greater than 3 volts at the Transmission Control Relay Output terminal of the TCM prior to the TCM energizing the relay.

POSSIBLE CAUSES
- INTERMITTENT WIRING AND CONNECTORS
- TRANSMISSION CONTROL RELAY STUCK CLOSED
- TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT SHORT TO VOLTAGE
- TRANSMISSION RELAY CONTROL CIRCUIT SHORT TO VOLTAGE
- TCM - TRANSMISSION RELAY ALWAYS ON