Pinpoint Test E: DTC B2574 Or B2575
Locks, Latches and Entry Systems
Pinpoint Tests
Pinpoint Test E: DTC B2574 or B2575
Refer to Wiring Diagram Set 110, Power Door Locks for schematic and connector information. Diagrams By Number
Normal Operation
The SJB sends voltage signals to the door lock control switches through circuits CPL42 (GY/YE) and CPL43 (VT/GY) for the lock and unlock requests. When the lock or unlock switch is pressed, the voltage signal is routed to ground. Ground for the LH door lock control switch is provided through circuit GD133 (BK). Ground for the RH door lock control switch is provided through circuit GD151 (BK/GN).
- DTC B2574 (Drivers Door LOCK Switch Short to Ground) - an on-demand DTC that sets when the SJB detects a short to ground from the lock request input circuit CPL42 (GY/YE).
- DTC B2575 (Drivers Door UNLOCK Switch Short to Ground) - an on-demand DTC that sets when the SJB detects a short to ground from the unlock request input circuit CPL43 (VT/GY).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Door lock control switch
- SJB
PINPOINT TEST E: DTC B2574 OR B2575
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
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E1 CHECK THE RECORDED SJB DTCs FROM THE SELF-TEST
- Check the recorded results from the SJB self-test.
- Is DTC B2574 or B2575 present?
Yes
GO to E2.
No
GO to Symptom Chart. Symptom Related Diagnostic Procedures
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E2 CHECK THE LH DOOR LOCK CONTROL SWITCH
- Disconnect: LH Door Lock Control Switch C505.
- Clear the DTCs and repeat the SJB self-test.
- Is DTC B2574 or B2575 present?
Yes
LEAVE the switch disconnected. GO to E3.
No
INSTALL a new LH door lock control switch. REFER to Door Lock Control Switch Service and Repair. TEST the system for normal operation.
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E3 CHECK THE RH DOOR LOCK CONTROL SWITCH
- Disconnect: RH Door Lock Control Switch C605.
- Clear the DTCs and repeat the SJB self-test.
- Is DTC B2574 or B2575 present?
Yes
LEAVE the switch disconnected. GO to E4.
No
INSTALL a new RH door lock control switch. REFER to Door Lock Control Switch Service and Repair. TEST the system for normal operation.
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E4 CHECK THE LOCK INPUT CIRCUIT OR THE UNLOCK INPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: SJB C2280b.
- For DTC B2574, measure the resistance between the LH door lock control switch C505-1, circuit CPL42 (GY/YE), harness side and ground.
- For DTC B2575, measure the resistance between the LH door lock control switch C505-3, circuit CPL43 (VT/GY), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to E5.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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E5 CHECK FOR CORRECT SJB OPERATION
- Disconnect all the SJB connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new SJB. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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