P0789Shift Timing Solenoid A Intermittent
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- 'Shift timing solenoid' means different parts: on GM's 4L60-E the 3-2 downshift solenoid that times the band apply on that downshift, on Aisin five-speeds (GM, Saab) the linear valve SLS that sets clutch pressure during the shift, and on the 2017–18 Genesis G80/G90 with shift-by-wire the on/off solenoids that engage drive (A) and reverse (B). P0789 is an intermittent fault in the circuit of solenoid A. No manufacturer document available to us uses it; manufacturers report the circuit under the base, low and high codes. A loose contact or a coil with heat-dependent dropouts is the likely cause; shift jolts and the warning lamp appear at times.
- What you may notice
- Shift jolts at times
- Warning lamp comes and goes
- Likely causes
- LikelyLoose contact at connector or harness
- PossibleCoil with thermal dropouts
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.