Pinpoint Test An: LFC 14/DTC U2023 - Fault Received From External Node

WARNING: This page is about a different car, the 2006 Mercury Montego, 2006 Ford Freestyle, and 2006 Ford Five Hundred. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough Inspection and Verification before proceeding with the pinpoint test.

AN1 CHECK FOR CONTINUOUS AND ON-DEMAND DTCs
WARNING:
1. Restraint system diagnostic tools are for service only. Tools must be removed prior to operating the vehicle over the road. Failure to remove restraint system diagnostic tools could result in injury and possible violation of vehicle safety standards.
2. Do not handle, move or change the original horizontal mounting position of the restraints control module (RCM) while the RCM is connected and the ignition switch is ON. Failure to follow these instructions may result in the inadvertent deployment of the safety canopy and risk of personal injury.
3. Never probe the connectors on the air bag module. Doing so can result in air bag deployment, which can result in personal injury.
4. The safety belt pretensioner is a pyrotechnic device. Always wear safety glasses when repairing an air bag equipped vehicle and when handling a safety belt buckle pretensioner or safety belt retractor pretensioner. Never probe a pretensioner electrical connector. Doing so could result in pretensioner or air bag deployment and could result in personal injury.
5. Never probe the electrical connector on a safety canopy module. Doing so can result in safety canopy deployment.
NOTE:
1. If a seat equipped with a supplemental restraint system (SRS) component is being serviced, the SRS must be depowered.
2. After diagnosing or repairing an SRS, the restraint system diagnostic tools must be removed before operating the vehicle over the road.
3. The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
- Enter the following diagnostic mode on the scan tool: Retrieve/Record Continuous DTCs.
- Was DTC U2023 retrieved during the on-demand self test?
Yes: This is a hard fault. The fault condition is still present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test.

GO to AN2.

No: This is an intermittent fault. The fault condition is not present at this time. GO to AN3.
AN2 CHECK THE HS-CAN NETWORK
- Enter the following diagnostic mode on the scan tool: Data Link Diagnostics.
- Did the Data Link Diagnostics test pass?
Yes: INSTALL a new RCM. REFER to RESTRAINTS CONTROL MODULE (RCM) . GO to AN4.

No: REFER to COMMUNICATIONS NETWORK . GO to AN4.
AN3 CHECK FOR AN INTERMITTENT FAULT
- Key in OFF position.
- Enter the following diagnostic mode on the scan tool: On-Demand Self Test.
- Was DTC U2023 retrieved during the on-demand self test?
Yes: This is a hard fault. The fault condition is now present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test. GO to AN2.

No: CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. REPAIR any intermittent concerns found. GO to COMMUNICATIONS NETWORK .
AN4 CHECK FOR ADDITIONAL DTCs
- Refer to the continuous DTCs recorded during Step AN1.
- Were any continuous DTCs retrieved during Step AN1 ?
Yes: Do not clear any DTCs until all DTCs have been resolved. GO to the RESTRAINTS CONTROL MODULE (RCM) DIAGNOSTIC TROUBLE CODE (DTC) TABLE for pinpoint test direction.

No: RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION . REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING . PROVE OUT the system. CLEAR all DTCs.