Hummer H2. Manual — part 570

The motor control circuit monitored by the driver seat module is determined to be shorted to ground, battery
positive voltage, or open.

Action Taken When the DTC Sets

z

The seat motor with a current status DTC will be disabled.

z

When the fault is no longer present a history status DTC will be stored, and motor operation will be
restored.

Conditions for Clearing the DTC

z

The DTC will be current for as long as the fault is present.

z

When the fault is no longer present the DTC will be a history status code.

z

The history DTC will be cleared after 100 error free ignition cycles, or by using the scan tool clearing
DTCs feature.

Diagnostic Aids

When an adjuster motor control circuit is shorted to ground the driver seat module will also set a DTC B3962.

DTC B1770, B1775, B1780, B1785, B1790, B1805, or B2415

Step

Action

Yes

No

Schematic Reference:Driver Seat Schematics
Connector End View Reference:Power Seat Systems Connector End Views

1

Did you perform the Power Seat Diagnostic
System Check?

Go to Step 2

Go to Diagnostic

System Check -

Power Seat

Systems

2

Verify the fault is present.
Does the system operate normally?

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

Go to Step 3

3

1. Disconnect the appropriate seat adjuster

motor connector.

2. Connect a test lamp across the adjuster

motor control circuit terminals in the harness
connector.

3. Operate the appropriate seat adjuster switch

in both directions.

Does the test lamp illuminate when the switch is
activated in both directions?

Go to Step 5

Go to Step 4

4

Test the motor control circuits for an open or short
to ground. Refer to Circuit Testing and to Wiring
Repairs in Wiring Systems.

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Seats - Hummer H2

DTC B1825

Circuit Description

The seat recline motor is equipped with a potentiometer type position sensor used by the driver seat module to
determine the position of the seat back. The motor position sensor is supplied with 5-volt reference and ground
circuits from the driver seat module. The position sensor signal circuit is referenced from ground within the
driver seat module. The signal voltage monitored by the driver seat module ranges from 0.39-4.58 volts and is
determined by the wiper location on the resistor within the motor position sensor. The position sensor circuit
voltage level is used by the driver seat module to determine the position of the seat back when storing or
recalling memory position settings.

Conditions for Running the DTC

The system voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC

The recline motor position sensor signal circuit voltage level to the driver seat module is not within the 0.39-
4.58 volt range.

Did you find and correct the condition?

Go to Step 9

Go to Step 6

5

Inspect for poor connections at the adjuster motor
connector. Refer to Testing for Intermittent
Conditions and Poor Connections and to
Connector Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Inspect for poor connections at the harness
connector of the driver seat module. Refer to
Testing for Intermittent Conditions and Poor
Connections and to Connector Repairs in Wiring
Systems.
Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the appropriate adjuster motor assembly.
Refer to Seat Adjuster Motor Replacement -
Front .
Did you complete the replacement?

Go to Step 9

-

8

Replace the driver seat module. Refer to Memory
Seat Control Module Replacement .
Did you complete the replacement?

Go to Step 9

-

9

1. Use the scan tool in order to clear the DTCs.

2. Operate the vehicle within the Conditions for

Running the DTC.

Does the DTC reset?

Go to Step 3

System OK

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Seats - Hummer H2

Action Taken When the DTC Sets

The recline motor will not function during memory or exit position recall operation.

Conditions for Clearing the DTC

z

The DTC will be current for as long as the fault is present.

z

When the fault is no longer present the DTC will be a history status code.

z

The history DTC will be cleared after 100 error free ignition cycles, or by using the scan tool clearing
DTCs feature.

Diagnostic Aids

A short to voltage on a sensor signal circuit or an open ground may effect other sensors using common 5-volt
reference and ground circuits causing the following DTCs to set:

z

B2435

z

B2440

z

B3606

Test Description

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

3: Tests for the proper operation of the signal circuit in the low voltage range.

4: Tests for the proper operation of the signal circuit in the high voltage range.

5: Tests for a short to voltage in the 5-volt reference circuit.

DTC B1825

Step

Action

Values

Yes

No

Schematic Reference:Driver Seat Schematics
Connector End View Reference:Power Seat Systems Connector End Views

1

Did you perform the Power Seat Systems
Diagnostic System Check?

-

Go to Step 2

Go to Diagnostic

System Check -

Power Seat

Systems

2

1. Install a scan tool.

2. With a scan tool, observe the Recline

Position Sensor parameter in the driver
seat module Sensor Data list.

Is the Recline Position Sensor parameter
within the specified range?

0.39-

4.58 V

Go to Testing for

Intermittent

Conditions and Poor

Connections in Wiring

Systems

Go to Step 3

1. Disconnect the recline motor position

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Seats - Hummer H2

3

sensor.

2. With a scan tool, observe the Recline

Position Sensor parameter.

Is the Recline Position Sensor parameter less
than the specified value?

0.39 V

Go to Step 4

Go to Step 8

4

1. Connect a 3-ampere fused jumper wire

between the signal circuit of the recline
position sensor and the 5-volt reference
circuit of the recline position sensor.

2. With a scan tool, observe the Recline

Position Sensor parameter.

Is the Recline Position Sensor parameter
greater than the specified value?

4.58 V

Go to Step 5

Go to Step 7

5

1. Disconnect the fused jumper wire.

2. Measure the voltage between the 5-volt

reference circuit of the recline position
sensor and the signal circuit of the
recline position sensor.

Is the recline position sensor parameter
greater than the specified value?

5 V

Go to Step 6

Go to Step 10

6

Test the 5-volt reference circuit of the recline
position sensor for a short to voltage. Refer to
Circuit Testing and to Wiring Repairs in
Wiring Systems.
Did you find and correct the condition?

-

Go to Step 15

Go to Step 12

7

Test the 5-volt reference circuit of the recline
position sensor for one of the following
conditions:

z

A short to ground

z

A high resistance

z

An open

Refer to Circuit Testing and to Wiring
Repairs in Wiring Systems.
Did you find and correct the condition?

-

Go to Step 15

Go to Step 9

8

Test the signal circuit of the recline position
sensor for a short to voltage. Refer to Circuit
Testing and to Wiring Repairs in Wiring
Systems.

-

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Seats - Hummer H2