DTC B3797
Diagnostic Instructions
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: |
| ⇒ |
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.
|
