Code result
P0891
TCM Power Relay Sense Circuit High
Moderate severity
What it means
The TCM detects voltage on the relay sense line above threshold while relay is commanded open, indicating relay welded closed or short to power.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Relay contacts welded
highOne of the most commonly reported causes for this code — check this first.
Wiring shorted to battery
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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