Workshop Manuals Factory service & repair Vauxhall
Vauxhall Astra J05 · Body Systems
05 · Body & interior

DTC B3797

Make
Vauxhall
Model
Astra J
Section
Vehicle Access › Other Information › DTC B3797
Body SystemsDTC B3797

DTC B3797

Diagnostic Instructions

•  Perform the prior to Diagnostic System Check - Vehicle using this diagnostic procedure.
•  Review Strategy Based Diagnosis for an overview of the diagnostic approach.
•  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B3797 02: All Door Dead Lock Circuit Short to Ground

Diagnostic Fault Information



Circuit
Short to Ground
Open/High Resistance
Short to Voltage
Signal Performance

Doors Lock Relay Control
B3797 02
1
1
-

Doors Lock Relay Ground
-
1
-
-

1. Door Dead Lock Malfunction
 

Circuit/System Description

Door latch assemblies each contain a reversible dead lock motor, each dead lock motor is controlled by 2 circuits; the dead lock control circuit and the dead lock unlock control circuit. To dead lock a door, the body control module (BCM) locks the door by momentarily energizing the door lock security relay. To complete the dead locking, the BCM momentarily applies voltage to the dead lock control circuit and ground to the door lock relay control circuit and the door latches will then dead lock.

To undead lock the door, the BCM uses the same circuit as the normal door unlocking system and the dead locks will unlatch with the rest of the door locks.

Conditions for Running the DTC

When the BCM commands the door dead lock.

Conditions for Setting the DTC

The BCM detects a short to ground in the door lock relay control circuit.

Action Taken When the DTC Sets

The dead locks will be inoperative

Conditions for Clearing the DTC

•  The DTC will be current for as long as the fault is present.
•  When the fault is no longer present, the DTC will be a history DTC.
•  A history DTC will clear after 50 ignition cycles.

Reference Information


Schematic Reference

Door Lock/Indicator Schematics


Connector End View Reference

Component Connector End Views


Description and Operation

Power Door Locks Description and Operation


Electrical Information Reference


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Command the doors to LOCK with a scan tool and manually unlock each door, attempt to open the door by using the exterior door handles. The exterior door handles should be inoperative.

Circuit/System Testing

1. Ignition OFF, disconnect the KR97 door lock relay.
2. Test for less than 10 Ω between the ground circuit terminal 85 and ground.
⇒ If greater than the specified range, test the ground circuit for an open/high resistance.
3. Connect a test lamp between the control circuit terminal 86 and ground.
4. Ignition ON, command the door dead locks to LOCK and UNLOCK with a scan tool, the test lamp should briefly illuminate when changing between the commanded states.
⇒ If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM
5. Verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
⇒ If the test lamp illuminates, test the control circuit for a short to voltage.
6. If all circuits test normal, replace the KR97 door lock relay.

Component Testing

Relay Test

1. Ignition OFF, disconnect the KR97 door lock relay.
2. Test for 60-200 Ω between terminals 85 and 86.
⇒ If not within the specified range, replace the KR97 door lock relay.
3. Test for infinite resistance between the following terminals:
  •  30 and 86
  •  30 and 87
  •  30 and 85
  •  85 and 87
⇒ If less than the specified value, replace the KR97 door lock relay.
4. Test for less than 2 Ω between terminals 30 and 87A.
⇒ If greater than the specified range, replace the KR97 door lock relay.
5. Install a 3 A fused jumper wire between the relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.
⇒ If greater than specified range, replace the KR97 door lock relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•  Control Module References for BCM replacement, setup, and programming

Parts & tools for this job For Vauxhall Astra

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