P0812
PowertrainTransmissionmoderate severityReverse Input Circuit
What P0812 Means
A fault was detected in the reverse input signal circuit to the transmission control system. This can affect reverse gear engagement and reverse-related functions.
Symptoms
- No or delayed reverse engagement
- Reverse lights malfunction
- Warning light illuminated
Common Causes
- Faulty reverse switch or sensor
- Wiring or connector fault
- Short or open in reverse circuit
- Control module fault
Diagnostic Steps
- Read transmission fault codes
- Inspect reverse switch and wiring
- Verify signal when selecting reverse
- Repair circuit or replace switch
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ANCEL AD410 →
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Serious DIY~$100
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Autel MaxiCOM MK808S →
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Autel MaxiSys MS906 Pro →
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✓ Autel official store
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