Code 81, 2-3 Shift Solenoid Circuit Fault: Notes

The PCM continually monitors voltage on each circuit connected to the quad-driver, looking for either low or high voltage, depending on the commanded state of the devices connected to it. Code 81 will set if a fault has been detected on the 2-3 shift solenoid circuit.

If 2-3 shift solenoid is commanded on by the PCM, voltage on that circuit should drop when solenoid is grounded. If 2-3 shift solenoid is off, voltage on the circuit should remain high. If solenoid is shorted off, 3rd gear only will occur. If solenoid is shorted on, 2nd gear only will occur. If voltage stays up for at least 2 seconds, Code 81 will set. If voltage drops for more than 2 seconds, Code 81 will set.

1. This test checks 2-3 shift solenoid and internal transmission wiring for short circuits.
2. This test checks for power, from the ignition through the fuse, to the shift solenoid.
3. This test ensures circuit No. 1223 is not shorted to ground.
4. This test checks ability of PCM to ground or control 2-3 shift solenoid. If bidirectional scan tester is not available, solenoid may be activated by grounding ALDL test terminal "B" with ignition on and engine off.