The 4L60E governor pressure switch is part of the PSM (pressure switch manifold). It tells the TCM what gear the trans is in based on hydraulic pressure. When it fails, you get codes and shift issues.
What it does
- Reads hydraulic pressure from specific circuits
- Reports gear position to TCM
- Combined signals tell TCM 1st, 2nd, 3rd, 4th, R, P/N
Symptoms of failure
- P0815, P0816, P0817 codes
- Wrong gear reporting
- Sometimes limp mode
- TCC issues
- Read our 4L60E common failure codes
Where it lives
- On valve body / pressure manifold
- Inside the trans (pan-off access)
- Multiple pressure switches in one assembly
Replacement
- Drop pan
- Remove filter
- Remove valve body bolts (note positions)
- Replace PSM
- Reinstall and refill
- Time: 4-6 hours
- Read our 4L60E shift solenoid B (similar procedure)
Cost
- PSM: $100-$200
- Filter, gasket, fluid: $80-$120
- DIY total: $180-$320
- Shop total: $400-$700
Pair with full pack rebuild
- If multiple solenoid codes: replace pack + PSM together
- Cost-effective long-term
- Read our best 4L60E rebuild kit
After replacement
- Clear codes
- TCM adapt cycle (50-100 miles)
- Verify codes don't return
- Read our transmission rebuild break-in
Need 4L60E PSM or pack parts? Shop our 4L60E catalog. Pressure switches, solenoids, rebuild kits. Free shipping over $70.
Related: