P0753

WITH 4L60-E AUTOMATIC TRANSMISSION

DTC P0753 Shift Solenoid 1-2 - Electrical:

Shift Solenoid 1-2 - Electrical:

Command Chart:

CIRCUIT DESCRIPTION
The 1-2 shift solenoid is used to control fluid flow acting on the 1-2 and 3-4 shift valves. The solenoid is a normally open exhaust valve that is used with the 2-3 shift solenoid to allow four different shifting combinations. The solenoid is attached to the control valve body within the transmission. Ignition voltage is supplied directly to the 1-2 shift solenoid. The Vehicle Control Module (VCM-A) controls the solenoid by providing the ground path through CKT 1222. DTC Type (D).

DTC P0753 WILL SET WHEN
The VCM-A Commands the solenoid "ON" and voltage remains high (B+) for two seconds. The VCM-A commands the solenoid "OFF" and voltage remains low (zero volts) for two seconds.

ACTION TAKEN (VCM-A will default to)
The transmission will only allow second and third gear if voltage remains high (B+), or first and fourth gear if voltage remains low (zero volts). DTC P0753 will be stored in the VCM-A memory and will turn "ON" the MIL (Malfunction Indicator Lamp). Line pressure will be at maximum pressure, and there will be no TCC.

DTC PO753 WILL CLEAR DEFAULT ACTION WHEN
The fault condition(s) no longer exist, and the ignition switch is cycled "OFF" for five seconds then "ON".

DTC PO753 WILL PASS WHEN
- VCM-A will report a "PASS" when the 1-2 solenoid is commanded "ON" and volts drop to 0 volts for two seconds. The VCM-A commands the 1-2 solenoid "OFF" and volts increase to (B+) for two seconds.
- The VCM-A turns "OFF the Malfunction Indicator Lamp (MIL) after three consecutive ignition cycles with reported passes (if applicable).
- All enable criteria are met.

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This test checks the function of the 1-2 shift solenoid and the internal transmission wiring harness.
2. This test checks for power to 1-2 shift solenoid from the ignition through the fuse.
3. This test checks circuit 1222 from the transmission 20-way connector to the VCM-A for an open.
4. This test checks circuit 1222 from the transmission 20-way to the VCM-A for a short to ground.

DIAGNOSTIC AIDS
Check all connections for the transmission.
Refer to Intermittents.
An open in the ignition feed circuit can cause multiple DTC(s) to set.