P0812moderate severityPowertrain
Reverse Input Circuit
on 1998 Toyota Tacoma 2.7L I4 · RWD
What this code 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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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0005
Fuel Shutoff Valve A Control Circuit/Open