DTC 81, Solenoid "B" Circuit Fault (1993): Notes

The PCM/TCM 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. DTC 81 will set if a fault has been detected on the shift solenoid "B" circuit, also referred to as 2-3 shift solenoid. For example, if shift solenoid "B" is commanded on by the PCM/TCM, voltage on that circuit should drop when solenoid is grounded. If voltage remains high for at least 2 seconds, DTC 81 will set. The opposite is also true. If shift solenoid "B" is off, voltage on the circuit should remain high. If voltage drops for greater than 2 seconds, DTC 81 will set.

NOTE: Test numbers refer to numbers on diagnostic chart.

Test Number 1) This step checks shift solenoid "B" and circuits inside transmission for shorts.

Test Number 2) Battery voltage should be present at shift solenoid "B".

Test Number 3) This step checks circuit No. 1223 for short to ground.

Test Number 4) This step checks if PCM/TCM can control solenoid "B". If bidirectional scan tool is not available, solenoid may be activated by grounding ALDL test terminal "B" with ignition on and engine off.

Test Number 5) This determines whether circuit No. 1223 is open or PCM/TCM is faulty.