Powertrain
Manufacturer-specific
OBD-II Fault Code
P1908: Transmission Pressure Circuit Solenoid Open or Short to Ground
Meaning, symptoms, likely causes, diagnostic checks and repair guidance for P1908.
Transmission / driveline
Use this category to narrow your checks before replacing parts.
High
Severity is a general guide. Confirm with scan-tool data and vehicle symptoms.
What P1908 usually means
Transmission Pressure Circuit Solenoid Open or Short to Ground.
Common symptoms
Check Engine light; Poor drivability or reduced fuel economy depending on fault; Harsh shifting, limp mode, slipping or delayed engagement possible
Likely causes
Low/dirty transmission fluid; Solenoid/valve body issue; Wiring fault; Internal transmission wear; Open circuit; Disconnected connector; Broken wire; Failed component; Wire shorted to chassis/ground; Internal component short
Diagnostic checks
Scan all modules and record freeze-frame data before clearing codes; Check battery voltage and related fuses; Check transmission fluid level/condition using correct procedure; Scan TCM data and inspect connector/wiring; Check connector fitment and continuity from module to component; Inspect harness for rubbing/pinch points and check resistance to ground
Repair guidance
Service/repair fluid or wiring issues first, test solenoid/valve body, seek transmission specialist for internal faults; Repair open wire/connector or replace the failed component after continuity test; Repair insulation/harness damage or replace internally shorted component
Verification after repair
Clear code, road-test through the same drive condition, then rescan