Automatic Ride Control: Other Ford Thunderbird X

QUICK TESTS

Note. Following quick tests and illustration are courtesy of Ford Motor Co.

Checking Steering Sensor

1. Wait until FIRM RIDE light turns off. With engine running and vehicle stopped, turn steering wheel from stop to stop 3 full times or until FIRM RIDE light comes on.
2. FIRM RIDE light normally comes on before steering wheel reaches one stop. If light comes on for 5 seconds and then goes out, proceed to TEST A3. If light does not come on, proceed to TEST D11.

Checking Speed Sensor

Wait until FIRM RIDE light turns off. Drive vehicle at more than 18 MPH (29 KM/H). If FIRM RIDE light comes on and stays on until vehicle speed is less than 18 MPH (29 KM/H), proceed to TEST A4. If FIRM RIDE light does not come on, proceed to TEST D16.

Checking Ride Control Switch

1. Ensure ride control switch is in AUTO position. After FIRM RIDE light turns off, place ride control switch in FIRM position. After FIRM RIDE light comes on, put ride control switch back to AUTO position.
2. If light is on in FIRM position and off in AUTO position, proceed to TEST A6. If light does not come on, proceed to TEST D19. If light flashes code, record trouble code and proceed to TROUBLE CODES under TESTING & DIAGNOSIS.

Checking Brake Sensor

1. Ensure ride control switch is in AUTO position. After FIRM RIDE light turns off, depress brake pedal firmly until light comes back on. After light comes on, release brake pedal.
2. If FIRM RIDE light comes on as described, proceed to TEST A7. If light does not come on as described, proceed to TEST D22. If light flashes code, record trouble code and proceed to TROUBLE CODES under TESTING & DIAGNOSIS.

Checking Acceleration Signal

1. Ensure ride control switch is in AUTO position. After FIRM RIDE light turns off, depress accelerator pedal to floor (with engine off as in TEST A4). FIRM RIDE light should come on.
2. Release accelerator pedal. FIRM RIDE light should turn off after 4 seconds. If light comes on and turns off as indicated, proceed to TEST A8. If light does not come on, proceed to TEST D25. If light flashes code, record trouble code and proceed to TROUBLE CODES under TESTING & DIAGNOSIS.

Checking Dimming Function

1. Move ride control switch to FIRM position. FIRM RIDE light should come on. Turn headlights on and off while watching FIRM RIDE light.
2. After TEST A1 through TEST A7 are completed, vehicle has passed diagnostics (no problem exists) if FIRM RIDE light is on bright with headlights off and is dimmer with headlights on. If FIRM RIDE light does not dim with headlights on, proceed to TEST C6.

Checking For Signal Return Continuity

1. Ensure ignition is off. Open trunk, and lower control module package tray behind left side of back seat. Disconnect 60-pin connector at ARC module.
2. Using DVOM to measure resistance, backprobe harness side of 60-pin connector between signal return pin No. 46 (circuit No. 837) and chassis ground. see scheme 2and (Scheme 8). If resistance is greater than 1000 ohms, repair open in circuit No. 837. If resistance is less than 10 ohms, proceed to TEST B3.

Energizing HARD RIDE Relay

1. Turn ignition switch to RUN position. At harness side of ARC module 60-pin connector, connect a jumper wire between pins No. 11 and 60 for 1-2 seconds. see scheme 2 Relay should energize.
2. Locate harness side of ARC module 60-pin connector. Using DVOM, check resistance between pins No. 46 and 19, 46 and 25, 46 and 7, and 46 and 10.
3. If resistance of any circuit is greater than 1000 ohms, circuit's position switch is open. If resistance of any circuit is less than 10 ohms, circuit's position switch is closed. If any individual switches are closed, locate which actuator is faulty, and proceed to TEST B5. If all 4 switches are open, proceed to TEST B4. If all 4 switches are closed, proceed to TEST B12.

Energizing SOFT RIDE Relay

1. Locate harness side of ARC module 60-pin connector. Connect a jumper wire between pins No. 12 and 60 for 1-2 seconds. see scheme 2 Relay should energize.
2. Locate harness side of ARC module 60-pin connector. Using DVOM, check resistance between pins No. 46 and 19, 46 and 25, 46 and 7, and 46 and 10.
3. If resistance of any circuit is greater than 1000 ohms, circuit's position switch is open. If resistance of any circuit is less than 10 ohms, circuit's position switch is closed.
4. If any individual switches are open, locate which actuator is faulty, and proceed to TEST B5. If all switches are closed or pin No. 10 is open, replace ARC module. If all 4 switches are open, proceed to TEST B12.

Actuator Resistance

1. Disconnect problem actuators harness connectors. (Scheme 8) Using a small-blade screwdriver, rotate control tube on problem actuators to "S" position.
2. Using DVOM, probe actuator connector terminals, checking resistance between signal return Yellow/Black wire and position sense wire of actuator. Position sense wire colors are White/Black on left front actuator, White/Red on right front actuator, White on right rear actuator and White/Orange on left rear actuator. Record resistance readings.
3. Rotate control tube to "H" position. Remeasure resistance of problem actuators. If resistance is greater than 1000 ohms, actuator switch is open. If resistance is less than 10 ohms, actuator switch is closed. If actuator switch is closed in "S" position and open in "H" position, proceed to TEST B9. If switch is always open or always closed, replace actuator.

Locating Actuator Connector Circuits. Scheme 8

Actuator Shorted Internally

1. Using a small-blade screwdriver, rotate actuator control tube to "H" position. Using DVOM, check resistance between soft power ("S") pin and position sense pin of actuator harness connector. Soft power ("S") pin wire color is Tan/Red for each actuator.
2. Position sense wire colors are White/Black wire on left front actuator, White/Red on right front actuator, White on right rear actuator and White/Orange on left rear actuator. If resistance is less than 10 ohms, replace actuator. If resistance is greater than 1000 ohms, proceed to TEST B10.

Signal Return Circuit Continuity

Using DVOM, check resistance between actuator harness connector terminal signal return Yellow/Black wire and chassis ground. If resistance is less than 10 ohms, proceed to TEST B11. If resistance is greater than 1000 ohms, check for open in Yellow/Black wire circuit. see scheme 2

Relay Power Circuit

Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect SOFT RIDE and HARD RIDE relay connectors. Turn ignition on. Using DVOM, check voltage from Black/Orange wire (power) to Black wire (ground) at both relay connectors. If voltage is zero volts, proceed to TEST B13. If voltage is 12 volts, proceed to TEST B14.

Relay Power Feed

Using DVOM, check voltage between Black/Orange wire and chassis ground at both relay connectors. If voltage is 12 volts, repair open in relay ground circuit (Black wire). If voltage is zero volts, check for blown shock fusible link in power distribution box or for open in Black/Orange wire power circuit.

Relays-To-Actuator Circuit Continuity

Disconnect right rear actuator harness connector. Using DVOM, check continuity of Tan/Black wire between actuator and HARD RIDE relay. Check continuity of Tan/Red wire between actuator and SOFT RIDE relay. If continuity exists, proceed to TEST B15. If continuity does not exist, repair defective wire circuit.

Crossed Relay Circuits

Ensure Light Green/Purple wire (circuit no. 838) and Tan/Black wire (circuit No. 845) are connected to HARD RIDE relay connector. Ensure Light Green/White wire (circuit No. 839) and Tan/Red wire (circuit No. 846) are connected to SOFT RIDE relay connector. If wire locations are correct, replace HARD RIDE relay; if wire locations are not correct, repair wiring as necessary. Go to TEST B16.

Relay Control Circuit Short

1. Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector. Ensure Light Green/Purple wire (circuit no. 838) is connected to pin No. 11 at ARC module connector. Ensure Light Green/White wire (circuit No. 839) is connected to pin No. 12 at ARC module connector.
2. At ARC module connector, use DVOM to check resistance between pins No. 11 and 60 and pins No. 12 and 60. (Scheme 8) If resistance in both circuits is greater than 1000 ohms, replace ARC module. If resistance is less than 10 ohms in either circuit, proceed to TEST B18.

Disconnect problem relay, and ensure wiring to relay is not crossed or damaged. If wires are crossed or damaged, repair wiring as necessary. If wiring is okay, proceed to TEST B19.

Retest Relay Control Circuit

At ARC module harness connector, use DVOM to check resistance between pins No. 11 and 60 and pins No. 12 and 60. If resistance in both circuits is greater than 1000 ohms, replace problem relay. If resistance in either circuit is less than 10 ohms, repair short in wiring.

Disconnect problem relay. Examine relay connector harness wires for obvious damage and crossed connections, and repair as required. If no problem is observed, proceed to TEST B23.

Coil Power Feed

Using DVOM, check voltage at Purple/Orange wire (circuit No. 298) of SOFT RIDE and HARD RIDE relays. If voltage is zero volts, repair or replace Purple/Orange wire between ARC module and relays. If voltage is 12 volts, proceed to TEST B24.

Relay Control Circuit

1. Check problem relay wiring circuit from relay connector to ARC module 60-pin connector. Using DVOM, check continuity of circuit No. 838 between ARC module connector pin No. 11 and HARD RIDE relay Light Green/Purple wire terminal. see scheme 2and (Scheme 8).
2. Check continuity of circuit No. 839 between ARC module connector pin No. 12 and SOFT RIDE relay Light Green/White wire terminal. If continuity exists (circuit is good) on both circuits, replace relay. If continuity does not exist (open circuit) on either circuit, repair wire as necessary, and proceed to TEST B25.

HARD RIDE Relay Position Switch

1. Attach problem actuator to shock absorber. See ACTUATORS under REMOVAL & INSTALLATION. Connect actuator to wiring harness. Turn ignition on. At ARC module 60-pin connector, connect a jumper wire between pins No. 11 and 60 for 2 seconds. HARD RIDE relay should energize.
2. Locate harness side of ARC module 60-pin connector. Check resistance between pins No. 46 and 19, 46 and 25, 46 and 7, and 46 and 10 using DVOM. see scheme 2
3. If resistance of any circuit is greater than 1000 ohms, circuit's position switch is open. If resistance of any circuit is less than 10 ohms, circuit's position switch is closed. If problem actuator position switch is open, proceed to TEST B26. If problem actuator position switch is closed, replace actuator and shock absorber (mechanical parts are binding).

SOFT RIDE Relay Position Switch

1. At ARC module 60-pin connector, connect a jumper wire between pins No. 12 and 60 for 2 seconds. SOFT RIDE relay should energize.
2. Locate harness side of ARC module 60-pin connector. Check resistance between pins No. 46 and 19, 46 and 25, 46 and 7, and 46 and 10 using DVOM. see scheme 2
3. If resistance of any circuit is greater than 1000 ohms, circuit's position switch is open. If resistance of any circuit is less than 10 ohms, circuit's position switch is closed. If problem actuator position switch is closed, replace ARC module. If problem actuator position switch is open, replace actuator and shock absorber (mechanical parts are binding).

Observing Key On Sequence

1. Turn ignition off. Place ride control switch in FIRM position. Shield FIRM RIDE light from bright light so FIRM RIDE light can be seen when dim. Turn ignition switch to RUN position.
2. If FIRM RIDE light does not come on, replace bulb, and proceed to TEST C2. If light is dim, proceed to TEST C5. If light comes on bright, proceed to TEST D1.

Module Power Circuit

1. Using DVOM, check voltage between pins No. 57 and 60 at ARC module 60-pin connector. see scheme 2 Replace ARC module if voltage is 12 volts.
2. If voltage is zero volts, check 18-gauge fusible link at starter solenoid and/or repair Purple/Orange wire (circuit No. 298). Circuit No. 298 goes through 8-pin junction connector in right kick panel.

FIRM RIDE Light Circuit

Locate FIRM RIDE light Dark Green/Light Green wire at instrument cluster connector. Using DVOM, check continuity of Dark Green/Light Green wire (circuit No. 419) from instrument cluster connector to pin No. 15 of ARC module connector. If continuity does not exist, repair Dark Green/Light Green wire as required. If continuity exists, check for fault in instrument cluster power, bulb and bulb ground.

Checking FIRM RIDE Light Dimming

Ensure ignition switch is in RUN position. Move ride control switch to FIRM position to turn on light. Turn headlight switch on and off while observing FIRM RIDE light. If light does not dim with headlights on, proceed to TEST C6.

FIRM RIDE Light Circuit Short

1. Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector.
2. At ARC module 60-pin connector, ensure Dark Green/Light Green wire (circuit No. 419) is securely attached to pin No. 15. Using DVOM, check resistance between pin No. 15 and pin No. 60 at harness side of 60-pin connector. If resistance is greater than 1000 ohms, replace ARC module. If resistance is less than 10 ohms, repair short to ground between ARC module and FIRM RIDE light.

Checking Switch Positions

Move ride control switch to FIRM position. If FIRM RIDE light stays on, proceed to TEST D6. If FIRM RIDE turns off, switch positions are reversed. Replace ride control switch.

Checking Brake Circuit For Short To Ground

1. Turn ignition off. Set ride control switch to AUTO position. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector. Ensure Orange wire (circuit No. 636) is securely attached to pin No. 9 of ARC module 60-pin connector.
2. Using DVOM, check resistance between pins No. 9 and 60 at ARC module 60-pin connector. If resistance is greater than 1000 ohms, proceed to TEST D7. If resistance is less than 10 ohms, repair short to ground in Orange wire between brake pressure switch and ARC module.

Brake Circuit Always Closed

Using DVOM, check resistance between pins No. 9 and 46 at ARC module 60-pin connector. If resistance is greater than 1000 ohms, proceed to TEST D8. If resistance is less than 10 ohms, replace brake pressure switch.

Ride Control Switch Circuit Closed

Ensure ride control switch is in AUTO position. Ensure Dark Green/Yellow wire (circuit No. 418) is securely attached to pin No. 18 at ARC module 60-pin connector. Using DVOM, check voltage between pins No. 18 and 60. If voltage is zero volts, proceed to TEST D9. If voltage is 12 volts, replace ride control switch.

Acceleration Signal Always Closed

Ensure Orange/White wire (circuit No. 836) is securely attached to pin No. 28 at ARC module 60-pin connector. Using DVOM, check resistance between pins No. 28 and 60. If resistance is greater than 1000 ohms, replace ARC module. If resistance is less than 10 ohms, proceed to TEST D10.

Acceleration Circuit Shorted

1. Turn ignition off. Disconnect EEC-IV control module from wiring harness. EEC-IV control module is located at right side cowling. Open trunk, and lower ARC module package tray behind left side of back seat.
2. Using DVOM, check resistance between pins No. 28 and 60 at ARC module harness connector. If resistance is greater than 1000 ohms, throttle position signal or EEC-IV module is defective. See appropriate TESTS W/CODES article in the ENGINE PERFORMANCE Section. If resistance is less than 10 ohms, repair short to ground in Orange/White wire (circuit No. 836) between ARC module and EEC-IV module.

Checking Steering Sensor Wires

Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector. At ARC module 60-pin connector, ensure Red wire (circuit No. 633) is securely attached to pin No. 45 and Brown wire (circuit No. 634) is securely attached to pin No. 24. Check for obvious damage to wires and connections, and repair as necessary. If damage is not apparent, proceed to TEST D12.

Note. Function will not be affected if circuits No. 633 and 634 are found to be reversed.

Steering Sensor Circuit Continuity

1. Turn ignition off. Disconnect steering sensor on lower steering column, near brake pedal. Check steering sensor wiring for obvious damage, and repair as necessary.
2. Using DVOM, check continuity of Red wire (circuit No. 633) from pin No. 45 of ARC module 60-pin connector to steering sensor connector. Also check continuity of Brown wire (circuit No. 634) from pin No. 24 of ARC module 60-pin connector to steering sensor.
3. If continuity does not exist in either check, repair open in Red or Brown wire as necessary. If no problem is found, proceed to TEST D14.

Steering Sensor Power

Turn ignition switch to RUN position. Check voltage between Purple/Orange wire terminal (circuit No. 298) and Yellow/Black wire terminal (circuit No. 837) of steering sensor connector using DVOM. If voltage is zero volts, proceed to TEST D15. If voltage is 12 volts, replace steering sensor.

Steering Sensor Circuit

Using DVOM, check voltage between chassis ground and Purple/Orange wire (circuit No. 298) of steering sensor connector. If voltage is zero volts, repair short or open in Purple/Orange wire. If voltage is 12 volts, repair open in Yellow/Black wire (circuit No. 837).

Speed Sensor Signal

1. Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector.
2. At ARC module 60-pin connector, ensure Dark Green/White wire (circuit No. 150) is securely attached to pin No. 3 and Black/White wire (circuit No. 359) is securely attached to pin No. 6. If wires have obvious damage, repair as necessary. If damage is not apparent, proceed to TEST D17.

Speed Sensor Ground

Using DVOM, check continuity of speed sensor Gray/Red ground wire (circuit No. 359) from pin No. 6 to pin No. 60 at ARC module 60-pin connector. If continuity exists, proceed to TEST D18. If continuity does not exist, repair open in Gray/Red wire or repair ground circuit No. 60 as necessary.

Speed Sensor

1. Check speedometer operation. If speedometer and speed sensor are okay, replace ARC module. If speedometer has an obvious problem, go to next step.
2. Raise vehicle, and disconnect transmission-mounted speed sensor harness connector. Using DVOM, check resistance between 2 wire terminals of sensor connector. If resistance is not 200-300 ohms, replace speed sensor.
3. If resistance is 200-300 ohms, connect DVOM on voltmeter (AC scale) between 2 wire terminals of sensor connector. With vehicle raised, operate rear wheels, and note if DVOM reading is 1.3-6.1 AC volts. If DVOM reading is zero AC volts, replace speed sensor.
4. If DVOM reading is 1.3-6.1 AC volts, ensure teeth of both speed sensor gears are in good condition. Also check speedometer fuse and wiring from sensor to ARC module and speedometer. Check instrument cluster circuit for loose screws, bad terminals and obviously damaged circuit board. If no problem is found, replace ARC module.

Checking FIRM Signal

1. Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector. At ARC module 60-pin connector, ensure Dark Green/Yellow wire (circuit No. 418) is securely attached to pin No. 18. Turn ignition on. Set ride control switch to FIRM position.
2. Using DVOM, check voltage between pins No. 18 and 60 at ARC module 60-pin connector. If voltage is zero volts, go to TEST D20. If voltage is 12 volts, replace ARC module.

Ride Control Switch

Turn ignition off. Disconnect ride control switch at instrument panel. Check wires at switch terminals for obvious damage. If wires are damaged, repair as necessary. If damage is not apparent, proceed to TEST D21.

Ride Control Switch Power Feed

Turn ignition switch to RUN position. Using DVOM, check voltage between chassis ground and Purple/Orange wire (circuit No. 298) of ride control switch harness connector. If voltage is zero volts, repair open or short in Purple/Orange wire. If voltage is 12 volts, replace ride control switch.

Brake Switch

1. Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector. Ensure Orange wire (circuit No. 636) is securely attached to pin No. 9 at ARC module 60-pin connector.
2. Have assistant start engine and press brake pedal firmly to floor. Using DVOM, check resistance between pins No. 9 and 60 at ARC module harness while brake pedal is depressed. If resistance is greater than 1000 ohms, proceed to TEST D23. If resistance is less than 10 ohms, replace ARC module.

Brake Pressure Switch Ground

Using DVOM, check resistance between ground and Yellow/Black wire terminal (circuit No. 837) of brake pressure switch harness connector. If resistance is less than 10 ohms, replace brake pressure switch. If resistance is greater than 1000 ohms, repair open or short in Yellow/Black wire.

Checking Module Connector

1. Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector.
2. Ensure Orange/White wire (circuit No. 836) is securely attached to pin No. 28 at ARC module 60-pin connector. Check for crossed wires and obvious damage. If wires are damaged, repair as necessary. If no problems are found, proceed to TEST D26.

Checking EEC-IV Connector

Turn ignition off. Disconnect 60-pin connector at EEC-IV module. Ensure Orange/White wire (circuit No. 836) is securely attached to pin No. 32 at EEC-IV module 60-pin connector. Check wiring for crossed wires and obvious damage. If wires are damaged, repair as necessary. If no problems are found, proceed to TEST D27.

Acceleration Circuit Continuity

Using DVOM, check Orange/White wire (circuit No. 836) from ARC module pin No. 28 to EEC-IV module pin No. 32 for continuity. If continuity does not exist, repair open in circuit between ARC and EEC-IV modules. If continuity exists, replace ARC module.

Checking Connector Wires

Turn ignition off. Ensure EVO valve connector on power steering pump is properly seated. Repair as required. If connector is properly seated, proceed to TEST E2.

Checking EVO Steering

1. Turn ignition off. Open trunk, and lower module package tray behind left side of back seat. Disconnect ARC module 60-pin connector.
2. Using DVOM, check continuity between pins No. 43 (Light Blue wire) and 48 (Yellow/Light Green wire). If resistance is less than 18 ohms or greater than 1000 ohms, proceed to TEST E3. If resistance is greater than 18 ohms or less than 1000 ohms, proceed to TEST E4.

Checking EVO Valve On Steering Pump

Disconnect EVO connector from EVO valve on power steering pump. Using DVOM, check resistance across both EVO valve connector pins. If resistance is less than 5 ohms or greater than 20 ohms, replace EVO valve. If resistance is greater than 5 ohms and less than 20 ohms, proceed to TEST E5.

BRAKE PRESSURE SWITCH