Detailed Service Procedure
WARNING:PRIOR TO PERFORMING ANY AIR BAG DIAGNOSTICS OR REPAIRS, BE SURE TO DEACTIVATE THE AIR BAG SYSTEM. ALSO, BE SURE TO CONNECT THE CORRECT AIR BAG SIMULATOR(S) IN PLACE OF THE DRIVER AND/OR PASSENGER AIR BAG(S).
1. Thoroughly check circuitry for any intermittent wiring shorts before attempting to replace the diagnostic monitor. Do not attempt to jump the thermal fuse with a circuit breaker or any other type fuse.
WARNING:
DO NOT INSTALL A NEW DIAGNOSTIC MONITOR UNTIL THE CAUSE OF FAULT CODE 51 HAS BEEN LOCATED AND REPAIRED. IF A SHORT-TO-GROUND HAS NOT BEEN LOCATED AND REPAIRED, THE SHORT IS INTERMITTENT AND IS NOT PRESENT AT THIS TIME. INSTALLING A NEW DIAGNOSTIC MONITOR WITH AN INTERMITTENT SHORT WILL RESULT IN REPEAT BLOWN INTERNAL THERMAL FUSES IN DIAGNOSTIC MONITORS AND REPEAT SERVICE.
2. Check the following locations for shorts-to-ground:
NOTE:
THE FOLLOWING ARE THE MOST COMMON LOCATIONS WHICH HAVE BEEN IDENTIFIED FOR INTERMITTENT WIRING SHORTS. IN THE EVENT INTERMITTENT WIRING SHORTS CANNOT BE FOUND AT THESE LOCATIONS, YOU MUST CHECK ALL OF THE AFFECTED WIRING AS REQUIRED.
^ Water may have entered the diagnostic monitor due to leaks near the monitor. Check for the following indicators:
^ A. Rust on the monitor's mounting bracket.
^ B. A white milky-colored substance on the printed circuit board in the monitor.
^ Condensation may have formed in the diagnostic monitor due to humidity in the air during A/C operation. Check for the following indicators:
^ A. Rust on the monitor's mounting bracket.
^ B. A white milky-colored substance on the printed circuit board in the monitor.
^ Wires may be pinched/cut between brake pedal mounting bracket and body.
^ Using a flashlight, inspect air bag wire harness routing along brake pedal mounting bracket (Figure 3).
^ Wires may be chafed or cut above the throttle pedal (Figure 4).
^ Using a flashlight, inspect air bag wire harness routing in area above throttle pedal (Figure 4).
^ Wires may be pinched/cut between instrument panel and body on RH side behind glove compartment.
^ Lower glove compartment door and RH instrument panel access cover. Using a flashlight, inspect air bag wire harness routing for pinch points and/or cuts (Figure 5).
^ Inspect wiring/wiring harnesses in areas where they pass through or are located next to metal components (i.e., engine compartment bulkhead, body sheet metal, component mounting brackets, etc.).
3. Any wiring on air bag system circuits may be repaired as follows:
a. If the insulation on any of the wires is nicked or cut, exposing bare wire, wrap affected area(s) with vinyl electrical tape.
NOTE:
USE FLAME RETARDANT VINYL ELECTRICAL TAPE FOR ANY REPAIRS IN THE ENGINE COMPARTMENT.
b. If wire(s) are only nicked, wrap affected area(s) with vinyl electrical tape.
c. If wire(s) are cut, proceed to Step 4.
4. Cut a piece of suitable length, same gauge replacement wire.
5. Slip Heat Shrink Tubing (WT-5627-A) over cut wire as shown in Figures 8-12.
6. Join replacement wire to existing cut wire and twist the ends together as shown in Figures 8-12.
NOTE:
BE SURE HEAT SHRINK TUBE IS ON CUT WIRE BEFORE SPLICING WIRES TOGETHER.
7. Using only 63/37 rosin core solder (do not use acid core), apply solder and heat to spliced wires.
WARNING:
USE ONLY A HEAT GUN. DO NOT USE A HAIR DRYER OR ANY FLAME TO HEAT THE SHRINK TUBE.
8. Position spliced wire so that shrink tubing can be positioned over soldered splice as shown in Figures 8-12.
9. Apply heat to shrink tube.
NOTE:
DO NOT OVERHEAT SHRINK TUBE. HEAT ONLY UNTIL ADHESIVE (HOT SEALANT) FLOWS FROM EACH END OF THE SHRINK TUBING AS SHOWN IN FIGURES 8-12. WHEN THE "HOT SEALANT" FLOWS FROM BOTH ENDS OF THE SHRINK TUBING, THE TUBING HAS BEEN HEATED ENOUGH AND AN ADHESIVE SEAL HAS BEEN FORMED BETWEEN THE HEAT SHRINK TUBE AND THE WIRE INSULATION.
10. Wrap the repaired area with vinyl electrical tape.
NOTE:
DO NOT ALLOW REPAIRED AREA TO COME IN CONTACT WITH ANY METAL SURFACES IN THE AFFECTED AREAS.
11. To avoid future contact with metal surfaces, perform the following:
a. Remove any existing burrs or sharp edges from metal surfaces that may come in contact with the repaired wiring.
b. Apply ordinary cloth tape to these areas.
c. Wrap nicked wiring with vinyl electrical tape.
d. Make sure wiring retainers are in the proper retaining holes.
e. Use an appropriate wiring retainer (chicken band) to pull wiring away from metal surfaces.
12. Replace the Air Bag Diagnostic Monitor (F32Z-14B056-A). Refer to the appropriate year Probe Service Manual, Section O1-20B, for removal and installation procedures.
WARNING:
CONNECT THE APPROPRIATE AIR BAG SIMULATOR TO AIR BAG WIRING BEFORE SYSTEM PROVE-OUT IS PERFORMED.
13. Reactivate the air bag system.
14. Perform the system prove-out as follows:
a. Turn ignition switch from OFF to RUN and visually monitor the air bag warning indicator. The air bag warning indicator will light continuously for approximately 6 seconds and then turn off.
If an air bag system fault is present, the air bag warning indicator will either fail to light, remain lit continuously or flash. The flashing may not occur until approximately 90 seconds after the ignition switch has been turned from OFF to RUN. This is the time required for the air bag diagnostic monitor to complete testing of the system.
If the air bag warning indicator is inoperative and an air bag system fault exists, a tone will sound in a pattern of five (5) sets of five (5) beeps. If this occurs, the air bag warning indicator will need to be serviced before further diagnosis can be done.
NOTE:
THE ABOVE INFORMATION IS ALSO GIVEN IN SECTION O1-20B OF THE APPROPRIATE YEAR PROBE SERVICE MANUAL.
WARNING:
REMOVE THE AIR BAG SIMULATOR AND RECONNECT THE AIR BAG(S) WHEN SYSTEM IS REACTIVATED.