B1336

DTC B1336

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



DTC Descriptor
DTC B1336
- Device Power 3 Circuit Range/Performance




Diagnostic Fault Information






Circuit/System Description

Battery positive voltage is supplied at all times to the memory seat module (MSM) through the battery positive voltage circuit from the POWER SEATS MSM circuit breaker located in the instrument panel (I/P) fuse block. This voltage is used to power up the MSM and also to apply power to the seat motors when commanded. The MSM applies voltage to the power seat motors through the motor control circuits. During memory recall and manual seat functions, the motor current is monitored through the motor control circuits by the MSM. When an overcurrent condition is detected by the MSM, the MSM will disable the seat motors in order to prevent the internal MSM circuitry from damage. The MSM is grounded through the module ground circuit at G301.


Conditions for Running the DTC

Battery voltage must be between 9-16 volts.


Conditions for Setting the DTC

DTC B1336 will set when the MSM detects a short to ground on a motor control circuit for 100 milliseconds or more.


Actions Taken When the DTC Sets

* The memory seat functions for the affected seat will be disabled.
* The MSM will disable manual movements of the affected motor.



Conditions for Clearing the DTC

* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.



Diagnostic Aids

The memory seat module (MSM) is also referred to as the driver position module (DPM) in certain scan tool menus.


Reference Information
Schematic Reference

Driver Seat Schematics (Driver Seat Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Memory Seats Description and Operation (Memory Seats Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)


Circuit/System Testing

1. Ignition ON, with a scan tool clear the current and history DTC.
2. Ignition ON, determine which motor set the DTC by operating the following motors one at a time in both directions. Check for the DTC to set between each motor test.

* Driver seat front vertical motor
* Driver seat rear vertical motor
* Driver seat horizontal motor

3. Ignition OFF, disconnect the X1 harness connector at the seat adjuster motor assembly.
4. Ignition OFF, test for less than 5.0 ohms of resistance between the UP/FORWARD control circuit and ground.

• If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuit tests normal, replace the MSM.

5. Ignition OFF, test for less than 5.0 ohms of resistance between the DOWN/REARWARD control circuit and ground.

• If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuit tests normal, replace the MSM.

6. Connect a test lamp between the motor control circuits of the inoperative motor.
7. Command the inoperative motor in both directions with a scan tool. The test lamp should turn ON when commanding the motor to both directions.

• If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuits test normal, replace the MSM.

8. If all circuits test normal, test or replace the seat adjuster motor assembly.



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Front Seat Adjuster Motor Replacement (Front Seat Adjuster Motor Replacement)
* Control Module References (Programming and Relearning) for MSM replacement, setup, and programming