4L60-E / 4L65-E Automatic Transmission

Diagnostic Chart:

Schematic:

Circuit Description with 4L60-E / 4L65-E Automatic Transmission
The Body Control Module (BCM) monitors the signal circuit of the Tow/Haul switch in order to determine when the switch is activated, requesting a trailering or hauling shift pattern.

CONDITIONS FOR RUNNING THE DTC
^ The battery voltage must be between 9.0 and 16.0 volts.
^ Ignition switch in the RUN position.
^ The Tow/Haul switch must be activated.

CONDITIONS FOR SETTING THE DTC
When the signal circuit of the Tow/Haul switch is shorted to ground for approximately 3 minutes. When the Tow/Haul switch is activated (stuck) for approximately 3 minutes.

ACTION TAKEN WHEN THE DTC SETS
Tow/Haul mode will be inoperative.

CONDITIONS FOR CLEARING THE DTC
^ This DTC will clear on current status after the condition for setting the fault is corrected.
^ A history DTC will clear after 100 consecutive ignition cycles without a fault present.
^ History and current DTC(s) may be cleared by using a scan tool.

DIAGNOSTIC AIDS
^ Perform a visual inspection for loose or poor connections at all related components.
^ Refer to Testing for Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
2. The normal state is the state of the input before activation
4. The normal state is the state of the input before activation
8. After replacement of the BCM you must calibrate the new module for proper operation.