DTC B2356 Driver Front Vert. Sensor Performance. GMC Truck Jimmy

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 1999 🢒 Jimmy - 4WD 🢒 DTC 🢒 DTC B2356 Driver Front Vert. Sensor Performance

Refer to

Cell 141: Memory Seat Module, Transducers and Motors

Power Seat Connector End Views
Handling ESD Sensitive Parts Notice
Power Seat Systems Components
Memory Seat Circuit Description
Cell 141: Power, Ground, DLC and Power Seat Adjuster Switch
Handling ESD Sensitive Parts Notice
.

Circuit Description

The memory seat module (MSM) monitors the seat front height motor position through the seat front height transducer CKT 557 (ORN/BLK). The MSM also sends a reference voltage on CKT 569 (RED) and provides a sensor ground (BLK).

Conditions for Setting the DTC

The DTC will set if the MSM detects that the seat front height sensor output voltage is either too high or too low due to the following conditions:

•	An open circuit

•	A short to ground

•	A short to power

•	A defective seat height transducer

Conditions for Clearing the DTC

•	A history DTC will clear after 100 consecutive fault free ignition cycles.

•	Use a scan tool in order to clear history and current DTCs.

Diagnostic Aids

One or more of the following conditions may be the cause of an intermittent failure:

•	A poor connection

•	A break in the wire insulation that exposes the internal wire

•	A wire broken inside the insulation

Test Description

The numbers below refer to the step numbers on the diagnostic table.

This step inspects for current DTCs.

This step inspects the wiring between the seat front height transducer and the MSM for open circuits.

This step repairs the open(s) in the wiring between the seat front height transducer and the MSM.

This step inspects the wiring between the seat front height transducer and the MSM for short(s) to ground.

This step repairs the short(s) to ground in the wiring between the seat front height transducer and the MSM.

This step verifies proper MSM operation.

This step replaces a defective seat front height transducer.

This step replaces a defective MSM.

Step

Action

Value(s)

Yes

Did you perform the Power Seat Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Power Seat Systems

Turn the ignition switch to the OFF position.
Install the scan tool.
Turn the ignition switch to the RUN position.
Using the scan tool, clear the DTCs.
Operate the MSM controls.

Does DTC B2356 reset?

Go to Step 3

Go to Diagnostic System Check - Power Seat Systems

Disconnect the MSM and the sensor.
Use a J 39200 digital multimeter (DMM) in order to test the continuity of each of the following circuits between the MSM connector and the seat front height transducer connector:

•	CKT 569 (RED)

•	CKT 557 (ORN/BLK)

•	CKT 569 (BLK)

Is continuity present on all circuits?

Go to Step 5

Go to Step 4

Locate and repair the open circuit(s).

Is the repair complete?

Go to Diagnostic System Check - Power Seat Systems

Disconnect the MSM.
Use a J 39200 digital multimeter (DMM) in order to test the continuity to ground of each of the following circuits at the MSM connector:

•	CKT 569 (RED)

•	CKT 557 (ORN/BLK)

•	CKT 569 (BLK)

Is continuity present on any circuit?

Go to Step 6

Go to Step 7

Locate and repair the short(s) to ground.

Is the repair complete?

Go to Diagnostic System Check - Power Seat Systems

Reconnect the MSM connector.
Disconnect the seat front height transducer.
Connect a J 39200 DMM between the CKT 569 (RED) and CKT 569 (BLK) terminals of the connector.

Does the voltage equal the specified value?

5 V

Go to Step 8

Go to Step 9

Replace the seat front height transducer.

Is the repair complete?

Go to Diagnostic System Check - Power Seat Systems

Replace the MSM.

Is the repair complete?

Go to Diagnostic System Check - Power Seat Systems