With 4L80 Transmission

DTC 81 2-3 Shift Solenoid Circuit Fault:

2-3 Shift Solenoid Circuit:

CIRCUIT DESCRIPTION
Ignition voltage is supplied directly to the 2-3 shift solenoid. The Powertrain Control Module (PCM) controls the solenoid by providing the ground path through CKT 1223.

DTC 81 WILL SET WHEN
^ The PCM commands the solenoid "ON" and voltage remains high.
^ The PCM commands the solenoid "OFF" and voltage remains low.
^ All conditions are met for 2 seconds.

ACTION TAKEN (PCM will default to)
^ Maximum line pressure.
^ No Torque Converter Clutch (TCC).
^ Second or third gear only.

DTC 81 WILL CLEAR WHEN
The fault condition(s) no longer exist, and the ignition switch is cycled "OFF" then "ON."

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks the function of the 2-3 shift solenoid and the internal transmission wiring.
2. This test checks for power to 2-3 shift solenoid from the ignition through the fuse.

DIAGNOSTIC AIDS
Check all connections at the transmission. Refer to "PCM Intermittent Diagnostic Trouble Codes or Performance." PCM/TCM Intermittent Diagnostic Trouble Code or Performance
An open in the ignition feed circuit can cause multiple DTC(s) to set.