| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. | 
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. | 
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. | 
The transmission mode switch signal enables the operator to achieve enhanced shift performance when towing or hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body control module (BCM) is momentarily toggled to 0 volts. This code sets when the rolling count of the transmission control module (TCM) does not match the same value sent from the BCM.
| • | The engine run time is greater than 5 seconds. | 
| • | The engine speed is between 500 and 6,500 RPM for 5 seconds. | 
The TCM detects an error in the rolling count value that does not match with the BCM.
| • | DTC P1762 is a type C DTC. | 
| • | The TCM forces normal shift operation. | 
DTC P1762 is a type C DTC.
Automatic Transmission Controls Schematics
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
Ignition ON, attempt to establish communication with the BCM using a scan tool.
| ⇒ | If no communication with the BCM, refer to Control Module References for further diagnosis. | 
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for TCM replacement, setup, and reprogramming.