Pinpoint Test I: Insufficient Heat During Engine Idle-3.9L Engine
WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
- I1 CARRY OUT THE DATC MODULE SELF-TEST
- Key in ON position.
- Carry out the DATC module self-test and retrieve continuous DTCs. Refer to CLIMATE CONTROL SYSTEM . Record the DTCs displayed, if any.
- Are any DTCs displayed?
- Yes : REFER to the DATC MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX . CARRY OUT the necessary diagnosis and REPAIR as necessary.
- No : GO to I2.
- I2 RECHECK DATC MODULE CONFIGURATION
- Enter Module Identification mode.
- Enter the following diagnostic mode on the scan tool: PID CNFG Data.
- Does the data read 4N_3N_2Y?
- Yes : GO to I3.
- No : RECONFIGURE the DATC module.
- I3 CHECK THE COOLANT LEVEL
- Check the coolant level with the engine at hot and cold temperatures.
- Is the engine coolant at the correct level (hot and cold)?
- I4 CHECK FOR AUXILIARY COOLANT PUMP OPERATION
- Connect the scan tool.
- Key in ON position.
- In the active command mode, request Climate Control System and select Pump/VCB or set driver side temperature to 32°C (90°F).
- Can the auxiliary cooling pump be heard running or be felt running?
- Yes : System is operating correctly.
- No : GO to 15.
- I5 CHECK THE AUXILIARY PUMP MOTOR
- Key in OFF position.
- Disconnect: Auxiliary Coolant Pump C163.
- Key in ON position.
- Make sure the active command Pump/VBC is still selected or the driver side temperature is set to 32°C (90°F).
- Measure the voltage between auxiliary coolant pump C163, circuit 30S-FB1 (RD/YE), harness side and circuit 31-FB1 (BK), harness side.
- Is the voltage greater than 10 volts?
- Yes : INSPECT terminals for damage and correct installation. If pins are installed correctly, INSTALL a new auxiliary coolant pump. TEST the system for normal operation.
- No : GO to I6.
- I6 CHECK CIRCUIT 31-FB1 (BK) FOR AN OPEN
- Measure the resistance between auxiliary coolant pump C163, circuit 31-FB1 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
- Yes : GO to I7.
- No : REPAIR circuit 31-FB1 (BK). TEST the system for normal operation.
- I7 CHECK THE AUXILIARY COOLANT PUMP RELAY
- Key in OFF position.
- Disconnect: Auxiliary Coolant Pump Relay C1005.
- Measure the voltage between CJB auxiliary coolant pump relay pins 2 and 5, circuit 30-FA74A (RD), harness side and ground.
- Is the voltage greater than 10 volts?
- Yes : GO to I8.
- No : REPAIR circuit 30-FA74A (RD). TEST the system for normal operation.
- I8 CARRY OUT THE RELAY COMPONENT TEST
- Carry out the relay component test. Refer to COMPONENT TESTING for component testing.
- Is the relay OK?
- Yes : GO to I9.
- No : INSTALL a new auxiliary coolant pump relay. TEST the system for normal operation.
- I9 CHECK CIRCUIT 30S-FB1 (RD/YE) FOR AN OPEN
- Disconnect: Auxiliary Coolant Pump Relay C1005.
- Measure the resistance between auxiliary coolant pump C163, circuit 30S-FB1 (RD/YE), harness side and auxiliary coolant pump relay pin 3, circuit 30S-FB1 (RD/YE), harness side.
- Is the resistance less than 5 ohms?
- Yes : GO to I10.
- No : REPAIR circuit 30S-FB1 (RD/YE). TEST the system for normal operation.
- I10 CHECK THE DATC MODULE
- Key in OFF position.
- Connect: Auxiliary Coolant Pump Relay C1005.
- Connect: Auxiliary Coolant Pump C163.
- Disconnect: DATC Module C228a.
- Disconnect: DATC Module C228b.
- Connect a fused jumper wire between DATC module C228b-18, circuit 91S-FA76 (BN/BU), harness side and DATC module C228a-2, circuit 31-FA10 (BK), harness side.
- Does the auxiliary coolant pump motor operate?
- Yes : INSPECT all connectors and terminals, RECONNECT the connectors, and TEST the system for normal operation. If condition still exists, INSTALL a new DATC module. TEST the system for normal operation.
- No : GO to I11.
- I11 CHECK CIRCUIT 91S-FA76 (BK/OG) FOR A SHORT TO POWER NOTE: If a short to power is found, it is necessary to install a new DATC module.
- Disconnect: Auxiliary Coolant Pump Relay C1005.
- Measure the voltage between auxiliary coolant pump relay pin 2, circuit 91S-FA76 (BK/OG), harness side and ground.
- Is any voltage present?
- Yes : REPAIR circuit 91S-FA76 (BK/OG). INSTALL a new DATC module. TEST the system for normal operation.
- No : GO to I12.
- I12 CHECK CIRCUIT 91S-FA76 (BK/OG) FOR AN OPEN
- Measure the resistance between auxiliary coolant pump relay circuit 91S-FA76 (BK/OG), harness side and DATC module C228b-18, circuit 91S-FA76 (BK/OG), harness side.
- Is the resistance less than 5 ohms?
- Yes : INSPECT all connectors and terminals, RECONNECT the connectors and TEST the system. If condition still exists, INSTALL a new DATC module. TEST the system for normal operation.
- No : REPAIR circuit 91S-FA76 (BK/OG). TEST the system for normal operation.