GM Service Manual Online
For 1990-2009 cars only

Circuit Description

DTC B1071 and/or B1075 indicates an internal supplemental restraint Diagnostic Energy Reserve Module (DERM) malfunction and sets when the DERM detects any of the following conditions:

    • The DERM energy reserve voltage discharge time fails for three consecutive ignition cycles (Turn On test).
    • The DERM cannot read from or write to the EEPROM (tested during the EEPROM read/write cycle)
    • The Driver 36 VLR power supply voltage measures above a specified value for 500 milliseconds (Continuous Monitoring test)
    • The DERM calculated number for the vehicle in which it is installed does not match the value stored in the EEPROM (Turn On test).

Conditions for Setting the DTC

The DTC sets when the DERM detects any of the indicated malfunctions. The DERM tests these conditions at different times:

  1. At Turn On test
  2. Asynchronously
  3. During Continuous Monitoring test
  4. At Turn On test

Action Taken When the DTC Sets

The DERM turns on the AIR BAG warning lamp and sets a diagnostic trouble code.

Conditions for Clearing the DTC

The DTC clears when the DERM does not detect the indicated malfunctions.

When measurements are requested in this table, use J 39200 Digital Multimeter with correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections in Section 8A4. When a wire, connector or terminal repair is requested, use J-38125 Terminal Repair Kit and refer to Wiring Repair.

DTC B1071- and/or DTC B1075- Internal DERM Fault

Step

Action

Value

Yes

No

1

Was the SRS Diagnostic System Check performed?

--

Go to Step 2

Go to SRS Diagnostic System Check

2

Replace the DERM. Refer to Supl Rst Diagnostic Energy Reserve Module .

Has the DERM been replaced?

--

Go to SRS Diagnostic System Check

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