P0788: Shift Timing Solenoid A High
What to do
Expect poor shift quality with all gears still available. Ask for the internal connector to be inspected rather than only the solenoid — corrosion there produces the same reading.
What this code means
The shift timing solenoid circuit is reading above its valid range — an open circuit or a short to supply, which are indistinguishable at the module. An internal connector that has corroded from fluid ingress reads exactly like a broken wire, and inside a transmission it is the more likely of the two.
Likely causes
Start here
- Open circuit in solenoid wiring · moderate
- Fluid tracking into the transmission connector · moderate
- Failed shift timing solenoid · moderate
Less common
- Wiring shorted to voltage · moderate
Symptoms
Components involved
Information, not instruction
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Community experience
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