LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2000 >> Contour SE, 2.5 L, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 109 (Supplemental Inflatable Restraint System) >> Diagnostic Tests >> Test Aa: Right Side Crash Sensor Communication Fault (DTC U2018) >> Possible Causes

Possible Causes

WARNING: This page is about a different car, the 2002 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

A right side crash sensor communication fault could be caused by damaged White wire (circuit No. 1263) or Brown wire (circuit No. 1264) or damaged right side crash sensor.

  1. Check for continuous or on-demand DTCs

    Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). See USING SCAN TOOL  under DIAGNOSTICS. Turn ignition switch to RUN position. Retrieve and record any continuous DTCs. See RETRIEVING FAULT CODES  under DIAGNOSTICS. Clear continuous DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS. Perform on-demand self-test. See ON-DEMAND SELF-TEST  under DIAGNOSTICS. If DTC U2018 was retrieved during on-demand self-test, go to next step. If DTC U2018 was not retrieved, fault is intermittent. Go to step  9 .

  2. Check side crash sensor harness connector

    Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Access right side crash sensor. See SIDE AIR BAG CRASH SENSOR  under REMOVAL & INSTALLATION. Ensure right side crash sensor harness connector is fully connected to sensor. If right side crash sensor is connected correctly, go to next step. If right side crash sensor is not properly connected, reconnect connector. Go to step  10 .

  3. Check circuit for open

    Turn ignition switch to OFF position. Access and disconnect RCM harness connector C2041B. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Disconnect right side crash sensor connector. Measure resistance of White wire between harness side of RCM connector C2041B, terminal No. 10 and harness side of right side crash sensor harness connector. See Figure . If resistance is more than one ohm, repair open in White wire. See WIRING DIAGRAMS  . Go to step  10 . If resistance is less than one ohm, go to next step.

  4. Check circuit for open

    Measure resistance in Brown wire between harness side of RCM connector C2041B, terminal No. 11 and harness side of right side crash sensor connector. If resistance is more than one ohm, repair open in Brown wire. Go to step  10 . If resistance is less than one ohm, go to next step.

  5. Check circuit for short to ground

    Disconnect RCM harness connector C2041A. Measure resistance between harness side of RCM connector C2041B, terminal No. 10 (White wire) and harness side of RCM connector C2041A, terminal No. 21 (Black wire, circuit No. 57). If resistance is less than 10 k/ohms, repair short to ground in White wire. Go to step  10 . If resistance is more than 10 k/ohms, go to next step.

  6. Check circuit for short to ground

    Measure resistance between harness side of RCM connector C2041B, terminal No. 11 (Brown wire) and harness side of RCM connector C2041A, terminal No. 21 (Black wire). If resistance is less than 10 k/ohms, repair short to ground in Brown wire. Go to step  10 . If resistance is more than 10 k/ohms, go to next step.

  7. Check circuit for short to battery or ignition

    Turn ignition switch to RUN position. Measure resistance between ground and harness side of RCM connector C2041B, terminal No. 10 (White wire). If voltage is more than 0.2 volt, repair short to battery or ignition in White wire. Go to step  10 . If voltage is less than 0.2 volt, go to next step.

  8. Check circuit for short to battery or ignition

    Measure voltage between ground and harness side of RCM connector C2041B, terminal No. 11 (Brown wire). If voltage is more than 0.2 volt, repair short to battery or ignition in Brown wire. Go to step  10 . If voltage is less than 0.2 volt, replace side crash sensor. Go to step  10 .

  9. Check for intermittent fault

    Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Refer to continuous DTCs recorded in step  1 . If DTC retrieved in step  1 was a intermittent fault, check for cause of intermittent communication fault. Attempt to recreate fault by flexing wire harness and cycling ignition switch frequently. Repair any intermittent problems found. Go to next step. If DTC retrieved in step  1 was not a intermittent fault, go to next step.

  10. Check for additional DTCs

    Refer to continuous DTCs recorded in step  1 . If any continuous DTCs were retrieved, go to diagnostic trouble code identification table for direction to appropriate test. DO NOT clear any DTCs until all DTCs have been resolved. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION  table. If no DTCs were retrieved, reconnect air bag system. Activate air bag system. See ACTIVATING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Clear all DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS.
scientia non olet · About LEMON Manuals