Circuit Description
Circuit A828 and X837 are the power supply feeds for transmission control module (TCM) keep-alive memory. The fused circuits supply constant voltage on terminals 26 and 54 of the TCM.
When the TCM detects that voltage has been interrupted on circuits A828 and X837, then DTC P1760 will set. DTC P1760 is a type D DTC.
Condition for Running the DTC
The ignition switch is in the RUN position.
Condition for Setting the DTC
The TCM detects a voltage interrupt.
Action Taken When the DTC Sets
| • | Early production - The TCM illuminates the service transmission lamp (STL). |
| • | Late production - The TCM flashes the Sport Mode Lamp. |
| • | The ECM records the operating conditions in the Failure Records at the time of the request from the TCM. |
| • | The TCM memory stores the DTC at the time of the first failure. |
| • | The TCM will restore RAM values from the EEPROM memory. |
Conditions for Clearing the DTC
| • | Early production - The TCM turns off the STL as soon as the fault is no longer present. |
| • | Late production - The TCM stops flashing the sport mode lamp as soon as the fault is no longer present. |
| • | A history DTC clears after forty consecutive warm-up cycles, if no failures are present by this diagnostic or any other emission related diagnostic. |
| • | The scan tool clears the DTC. |
| • | The TCM cancels the DTC default mode actions when the fault no longer exists and the ignition switch is off long enough in order to power down the TCM. |
Diagnostic Aids
Vehicles equipped with Fuel Cap Lamps utilize the Sport Mode lamp to indicate a transmission malfunction. In these vehicles, the Sport Mode Lamp flashes at 200 millisecond intervals when the TCM commands the lamp ON.
Vehicles not equipped with Fuel Cap Lamps are equipped with a dedicated Service Transmission Lamp (STL) on the Instrument Panel Cluster (IPC). The STL illuminates steadily when the TCM commands the lamp ON.
There may be no condition. If the power was interrupted for any reason, this DTC will set. Has the vehicles battery gone dead or required service recently? Has any other work been done that may have interrupted the power to the TCM? If no condition is found, the TCM may be the cause of the condition.
Use the J 35616-A connector test adapter kit for any test that requires probing the TCM harness connector or a component harness connector. Using this kit will prevent damage to the harness connector terminals.
Check for the following conditions:
| • | Poor connections at the TCM. Inspect the harness connectors for any backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. |
| Refer to General Electrical Diagnosis in Wiring Systems for proper procedure. |
| • | Damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving any related connectors and any wiring harnesses. A change in the display may help to locate the fault. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
A short to ground in circuit A828 would cause the Clamp 30 fuse to open.
-
Replace the TCM only after all other test procedures have been completed.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||||||||
Is the Scan Tool able to communicate with the TCM? | -- | Go to Diagnostic Aids | ||||||||
3 |
Does the test light illuminate on each terminal? | -- | ||||||||
4 | Inspect the TCM and the TCM connector for the following:
Did you find the condition? | -- | ||||||||
5 | Replace the TCM. Refer to Transmission Control Module Replacement . Is the replacement complete? | -- | -- | |||||||
Inspect the #5 A/T fuse and the #3 FLASHER fuse for an open. Did you find an open condition? | -- | |||||||||
7 | Inspect circuits A828 and X837 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
8 | Inspect circuits A828 and X837 for an open. Was the condition found? | -- | -- | |||||||
9 | Repair the circuits as necessary. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |||||||
10 | With the engine OFF, turn the ignition switch to the RUN position. Can the Scan Tool communicate with the TCM? | -- | ||||||||
11 |
Did the TCM DTC clear? | -- | System OK | -- |
