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Pinpoint Test G: The Doors Do Not Lock/Unlock Using The Keyless Entry Keypad




Handles, Locks, Latches and Entry Systems - Without Intelligent Access (IA)

Pinpoint Test G: The Doors Do Not Lock/Unlock Using The Keyless Entry Keypad

Refer to Wiring Diagram Set 117, Remote Keyless Entry and Alarm for schematic and connector information Electrical Diagrams.

Normal Operation

The Body Control Module (BCM) monitors for a ground signal on the keyless entry keypad signal input circuits. When an individual keypad button is pressed, an individual or combination of the input circuits is routed to ground. The BCM (Body Control Module) then determines which button was pressed based on which circuit(s) are grounded. The keypad has a dedicated ground circuit. Once the BCM (Body Control Module) determines that the 5-digit personal entry code, or the factory set 5-digit entry code has been entered on the keypad, the BCM (Body Control Module) energizes the driver door unlock relay to unlock the driver door (stepped unlock enabled).

To unlock all of the doors, press the 3/4 button within 5 seconds of entering the 5-digit code.

To lock all the doors, the 5-digit code does not need to be entered. Press the 7/8 and 9/0 buttons at the same time, with the driver door closed.

The keyless entry keypad has an anti-scan feature to prevent theft. If a valid 5-digit code is not entered within 7 attempts (35 consecutive button presses), the keyless entry keypad goes into anti-scan. In anti-scan mode, the keypad illumination flashes and all input is ignored except for pressing the 7/8 and 9/0 buttons, which locks all of doors.

- DTC B121B:01 (Keypad Input Switch: General Electrical Failure)- sets when the BCM (Body Control Module) detects a short to ground on any of the keyless entry keypad input circuits.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Keyless entry keypad

- BCM (Body Control Module)

PINPOINT TEST G : THE DOORS DO NOT LOCK/UNLOCK USING THE KEYLESS ENTRY KEYPAD

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

NOTE: Failure to disconnect the battery when instructed results in false resistance readings.

G1 CHECK THE BCM (Body Control Module) KEYPAD CODE

- Enter the following diagnostic mode on the scan tool: BCM (Body Control Module) DataLogger.

- Observe the BCM (Body Control Module) PIDs (KEYCODE_1stD, KEYCODE_2ndD, KEYCODE_3rdD, KEYCODE_4thD, and KEYCODE_5thD). Read and record the 5-digit factory set entry code.

- Enter the 5-digit factory set entry code on the keyless entry keypad.

Do the doors unlock?

Yes
The system is operating as designed. INFORM the customer of the correct system operation.

No
GO to G2.

G2 RETRIEVE THE RECORDED BCM (Body Control Module) DTCs FROM THE SELF-TEST

- Check for recorded BCM (Body Control Module) DTCs from the self-test.

Is DTC B121B:01 recorded?

Yes
GO to G3.

No
GO to G5.

G3 REPEAT THE BCM (Body Control Module) SELF-TEST

- Disconnect: Keyless Entry Keypad C500.

- Clear the DTCs, then repeat the BCM (Body Control Module) on-demand self-test.

Is DTC B121B:01 recorded?

Yes
GO to G4.

No
INSTALL a new keyless entry keypad. REFER to Keyless Entry Keypad . TEST the system for normal operation.

G4 CHECK THE KEYPAD INPUT CIRCUITS FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: BCM (Body Control Module) C2280C.

- Measure the resistance between the keypad, harness side and ground as follows:

Connector-Pin Circuit C500-7 CPK29 (GY/BU) C500-5 CPK30 (VT/GN) C500-1 CPK31 (YE/GN)






Are the resistances greater than 10,000 ohms?

Yes
GO to G10.

No
REPAIR the circuit in question for a short to ground. CLEAR the DTCs. REPEAT the self-test.

G5 CHECK THE BCM (Body Control Module) KEYPAD PIDs

- Enter the following diagnostic mode on the scan tool: BCM (Body Control Module) DataLogger.

- Press each keyless entry keypad button while observing the PIDs (KYPD_BTN_1/2, KYPD_BTN_3/4, KYPD_BTN_5/6, KYPD_BTN_7/8, and KYPD_BTN_9/0).

Do the PIDs display active when the corresponding button is pressed?

Yes
GO to G10.

No
GO to G6.

G6 CHECK THE KEYPAD GROUND CIRCUIT FOR AN OPEN

- Ignition OFF.

- Disconnect: Negative Battery Cable.

- Disconnect: Keyless Entry Keypad C500.

- Measure the resistance between the keyless entry keypad C500-2, circuit GD133 (BK), harness side and ground.






Is the resistance less than 5 ohms?

Yes
GO to G7.

No
REPAIR the circuit. TEST the system for normal operation.

G7 CHECK THE KEYLESS ENTRY KEYPAD

- Connect: Negative Battery Cable.

- Connect a fused jumper wire between the keyless entry keypad, harness side, while monitoring the BCM (Body Control Module) PIDs (KYPD_BTN_1/2, KYPD_BTN_7/8, and KYPD_BTN_9/0) as follows:

Keyless Entry Keypad Connector-Pin/Circuit Keyless Entry Keypad Connector-Pin/Circuit BCM (Body Control Module) PID C500-7 CPK29 (GY/BU) C500-2 GD133 (BK) KYPD_BTN_1/2 C500-5 CPK30 (VT/GN) C500-2 GD133 (BK) KYPD_BTN_7/8 C500-1 CPK31 (YE/GN) C500-2
GD133 (BK) KYPD_BTN_9/0






Do the PIDs display active when the jumper wire is connected?

Yes
INSTALL a new keyless entry keypad. REFER to Keyless Entry Keypad .

No
GO to G8.

G8 CHECK THE KEYPAD INPUT CIRCUITS FOR AN OPEN

- Disconnect: BCM (Body Control Module) C2280C.

- Measure the resistance between the BCM (Body Control Module), harness side and the keyless entry keypad, harness side as follows:

BCM (Body Control Module) Connector-Pin Circuit Keyless Entry Keypad Connector-Pin C2280C-24 CPK29 (GY/BU) C500-7 C2280C-18 CPK30 (VT/GN) C500-5 C2280C-11 CPK31 (YE/GN) C500-1






Are the resistances less than 5 ohms?

Yes
GO to G9.

No
REPAIR the circuit in question for an open. TEST the system for normal operation.

G9 CHECK THE KEYPAD INPUT CIRCUITS FOR A SHORT TO EACH OTHER

- Measure the resistance between the keypad, harness side as follows:

Keypad Connector-Pin/Circuit Keypad Connector-Pin/Circuit C500-7 CPK29 (GY/BU) C500-5 CPK30 (VT/GN) C500-7 CPK29 (GY/BU) C500-1 CPK31 (YE/GN) C500-5 CPK30 (VT/GN) C500-1 CPK31 (YE/GN)






Are the resistances greater than 10,000 ohms?

Yes
GO to G10.

No
REPAIR the circuits in question. TEST the system for normal operation.

G10 CHECK FOR CORRECT BCM (Body Control Module) OPERATION

- Disconnect all the BCM (Body Control Module) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the BCM (Body Control Module) 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 BCM (Body Control Module). 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.