Code result
P0816
Downshift Switch Circuit
Moderate severity
What it means
The TCM detects an electrical fault on the manual downshift request switch circuit.
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
Switch contacts failed
highOne of the most commonly reported causes for this code — check this first.
Wiring open
mediumA plausible cause — test and verify before replacing parts.
Related help
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