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

WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

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

I1 CHECK THE DTCs
- Enter the following diagnostic mode on the diagnostic tool: Retrieve DTCs
- Is DTC B2695, B2696, or B2697 present?
1. YES : Go to I2.
2. NO : Go to I4.

I2 CHECK THE KEYPAD INPUT TO THE SJB FOR A SHORT TO GROUND

Key in OFF position.
Disconnect: SJB C2280d

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

SJB Connector-Pin	Circuit
C2280d-6	78 (LB/YE)
C2280d-7	79 (LG/RD)
C2280d-8	121 (YE/BK)

Are the resistances greater than 10,000 ohms?

YES : Go to I7.
NO : Go to I3.

I3 CHECK CIRCUITS 78 (LB/YE), 79 (LG/RD) AND 121 (YE/BK) FOR A SHORT TO GROUND

Key in OFF position.
Disconnect: Keyless Entry Keypad C500

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

SJB Connector-Pin	Circuit
C2280d-6	78 (LB/YE)
C2280d-7	79 (LG/RD)
C2280d-8	121 (YE/BK)

Are the resistances greater than 10,000 ohms?

YES : INSTALL a new keyless entry keypad. REFER to Keyless Entry Keypad .
NO : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.

I4 CHECK CIRCUIT 570 (BK/WH) FOR AN OPEN
- Key in OFF position.
- Disconnect: Keyless Entry Keypad C500
- Measure the resistance between the keyless entry keypad C500-6, circuit 570 (BK/WH), harness side and ground.
- Is the resistance less than 5 ohms?
1. YES : Go to I5.
2. NO : REPAIR the circuit. TEST the system for normal operation.

I5 CHECK FOR REFERENCE VOLTAGE SIGNALS TO THE KEYPAD

Measure the voltage between the keyless entry keypad, harness side and ground as follows:

Keyless Entry Keypad Connector-Pin	Circuit
C500-1	78 (LB/YE)
C500-3	79 (LG/RD)
C500-7	121 (YE/BK)

Are the voltages greater than 5 volts?

YES : INSTALL a new keyless entry keypad. REFER to Keyless Entry Keypad . TEST the system for normal operation
NO : Go to I6.

I6 CHECK CIRCUITS 78 (LB/YE), 79 (LG/RD) AND 121 (YE/BK) FOR AN OPEN

Disconnect: SJB C2280d

Measure the resistance between the SJB, harness side and the keyless entry keypad, harness side:

SJB Connector-Pin	Keyless Entry Keypad Connector-Pin	Circuit
C2280d-6	C500-1	78 (LB/YE)
C2280d-7	C500-3	79 (LG/RD)
C2280d-8	C500-7	121 (YE/BK)

Are the resistances less than 5 ohms?

YES : Go to I5.
NO : REPAIR the circuit in question. TEST the system for normal operation.

I7 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?
1. YES : INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES article. TEST the system for normal operation.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.