Domestic Car Tech Tips

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CHRYSLER 1989-1994 - Many
Many 1989-1994 Chrysler products may produce a noise from the vicinity of the alternator that sounds like a bad bearing or electrical arcing. The noise is not necessarily caused by a failed alternator, but by a misaligned alternator pulley. To determine if the pulley is the source of the noise, spray the inside of the alternator drive belt with water while the engine is running. If the noise immediately disappears then gradually returns, belt misalignment is the cause. For 1989 and 1990 vehicles the cure is to fit a replacement alternator bracket (Chrysler part number 4556173). If the noise is still present, add the spacer (flat washer) listed below. 1991-1994 vehicles already have a redesigned bracket but may need to have a spacer (Chrysler part number 6500299) added next to the existing flat washer on the pivot through-bolt.

CHRYSLER 1995-1999 Avenger & Seabring 2.0L; 2.5L
1995-199 Dodge Avengers and Chrysler Seabrings may develop a wiring harness short circuit that causes one or more of the following:

  • Dead battery
  • No-start condition
  • Charging light stays on
  • ABASE warning light stays on

If these symptoms occur, and if the computer shows no trouble codes, check the wiring harness in the vicinity of the transmission shift lever. The harness runs very close to the lever at this point and, over time it may chafe against the lever enough to wear away the insulation and cause a short. If the harness is found to be damaged, repair or replace it as required and resecure it farther away from the shift lever.

CHRYSLER 1996-1997 Dodge Caravan, Plymouth Voyager 3.3L; 3.8L
1996-1997 Caravans, Voyagers and Town and Country mini-vans with the 3.3L and 3.8L engines may experience a problem where the starter partially disengages and then re-engages while cranking the engine. This may be accompanied by a noticeable pinion noise. The problem can be traced to a malfunctioning Powertrain Control Module (PCM). Repair involves replacing or reprogramming the PCM. To reprogram the PCM proceed as follows:

  1. Connect the MDS (Mopar Diagnostic System) and the DRB III (Scan Tool) to the vehicle and power up.

  2. Using the arrow keys, select #2 MDS Diagnostics on the DRB III Main Menu Screen.

  3. Select Diagnostics Menu on the MDS, and then press "Next Menu."

  4. Select Vehicle Controller Programming on the MDS, and then press "Next Menu".

  5. Select Programming of All Other Controllers With MDS & DRB on the MDS, and then press "Next Menu".

  6. Follow the prompts on the MDS and DRB III, which will allow the DRB III to obtain the current number of the PCM.

  7. The MDS will display the part number of the PCM on the vehicle and the appropriate part number, then press "Next Menu". NOTE: If the PCM has already been updated or programmed, "No Updates Available" message will appear. Check the part number of the PCM on the vehicle and compare it to the number displayed. If the PCM has already been updated, another problem exists that will require further diagnosis and repair.

  8. The MDS and DRB III will prompt for inputs required to complete the reprogramming process. NOTE: law requires the following steps:

  9. Type the necessary information on the "Authorized Software Update" label, part number 4669020. Attach the label to the PCM and cover the label with clear plastic overlay included.

  10. Type the necessary information on the "Authorized Modification" label and attach it near the VECI label.

CHRYSLER 1981-1987 LeBaron, New Yorker, Aries, Reliant, Caravan & Voyager 2.6L
Many Chrysler models with the 2.6L Mitsubishi engine may develop a no-start or low battery charge condition due to a faulty cooling fan switch relay. If the relay fails in the closed position, the fans will run constantly, whether the ignition is on or not. This can put enough of a load on the battery to completely discharge it in a matter of hours. If the vehicle is started, the alternator will be forced to work continuously at maximum output in order to recharge the battery. Under the best circumstances this will greatly shorten the alternator's life; at worst it may cause it to fail almost immediately. Always check the cooling fan relay when replacing the alternator on one of these vehicles. Install a new relay if there is any sign that the old one is not working properly.

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FORD 1992-1994 Explorer
1992-1994 Explorers may develop a no-start condition along with intermittent failure of headlights, instrument lights or other accessories. These same vehicles may also experience drivability problems including erratic idle, rough running and hesitation. Ford suggests that the battery cables and other wiring near the battery be inspected for corrosion or deterioration resulting from exposure to battery gasses. Swelling, discoloration, or a buildup of corroded material can identify damaged wires. In some cases wiring may be corroded almost completely through. Ford recommends replacement of any damaged wires with new and the installation of a redesigned battery cover (Ford part number F3TZ-10A687-A) to prevent a recurrence of the problem.

FORD 1990-1991 Explorer, Ranger, Ranger 4.0L
1990-1991 Explorer and Rangers with the 4.0L engine may develop a rough idle accompanied by a hard-start or no-start condition. The problem can be traced to a poor ground at the EDIS ignition module. To check quickly for a ground problem, locate the module's connector on the right-hand radiator support and wiggle it. If this results in an improved idle or easier starting, inspect the module's ground wire (black/light green for 1990; black/white for 1991) at the ground terminal. If the terminal does not have a brass sleeve Ford recommends installing a replacement terminal (Ford part number F1TZ-14461-A) to insure a good ground connection.

FORD 1991-1994 Ford, Lincoln, Mercury 4.6L
1991-1994 Fords, Lincolns and Mercurys with the 4.8L engine often develop an intermittent "no-start" condition where the starter fails to respond when the ignition key is turned. Often there is nothing wrong with the starter. The problem is caused by corrosion in the vehicle's wiring harness at the push-on connector to the starter solenoid. Whether you have experienced this problem or not, the connector must be inspected and, if necessary, replaced whenever the starter is serviced (use Ford part number F4VY-A411-A or equivalent).

FORD 1985-1991 "F" Series Trucks 4.9L; 5.0L w/Fuel Inj.
1985-1991 "F" series trucks with fuel injected 4.9L and 5.0L engines may develop a no-crank condition due to deterioration of a sliced connection in the engine compartment wiring harness. The connection is located under the breather box on the driver's side inner fender. Over time, water penetration can corrode the splice, causing a complete loss of power to the fuse panel. Repair the splice as required, making sure to reinsulate the wiring bundle carefully.

FORD 1990 Lincoln Town Car 3.8L; 5.0L
1990 Lincoln Town Cars with the 3.8L and 5.0L engine may develop a no-crank condition caused by the corrosion of the neutral safety switch contacts. Water droplets from the wiper module can leak into the transmission vent, contaminating the transmission fluid and leading to failure of the neutral safety switch. If the transmission fluid appears milky, it is likely contaminated with water. To eliminate the no-start problem, replace the neutral safety switch. Ford also recommends installation of a deflector kit, part number F0VY-17A500-A to prevent water from entering the vent tube.

FORD 1989-1992 Lincoln Town Car
1989-1992 Lincoln Town Cars may develop a no-start condition due to low battery charge. The ABS pump motor relay is subject to moisture contamination, which can corrode its contacts, causing it to remain running continuously. This can drain the battery, leading to a slow-crank or no-start situation, and can also cause the alternator to work at maximum output for extended periods thus causing premature failure. Installation of Ford relay kit number F0VY-14A303-A will relocate the relay to avoid recurrence of the problem.

FORD 1989-1992 Probe
1989-1992 Probes may experience premature alternator failure due to a constant electrical drain caused by one or both of the following problems:

A binding or misaligned hood release handle. The micro switch for the engine compartment light is part of the hood release handle on these vehicles. If the handle is misaligned or fails to return to its normal position, the light may remain on even though the hood has been closed tightly. The continuous draw of the light is enough to keep the battery in a constant state of discharge, forcing the alternator to operate continuously at full output as it attempts to recharge the battery as well as meet normal system demands. The solution is to place a thin washer between the backside of the dash and the retainer nut on the release cable. This will allow the handle to return to its normal position and switch off the light.

Corrosion in one or more of the main wiring harness connectors in front of the radiator or in the engine compartment. Water contamination in these connectors can cause short circuits or high resistance connections which can lead the battery drain, blown fuses, or problems with headlights, A/C or the heater fan relay. To correct the problem, all main connectors must be inspected carefully. Those showing evidence of corrosion or water damage must be thoroughly cleaned or replaced.

FORD 1989-1992 Probe 2.2L (Non-Turbo)
1989-1992 Probes with non-turbo 2.2L engine may experience a low battery charge condition if regularly driven short distances, at low speeds or in stop-and go traffic with heavy accessory loads. Under these conditions the engine does not turn the alternator fast enough to meet the demand on the electrical system and the battery must supply the difference. Over time, this imposes severe loads on the charging system, and can lead to premature alternator failure. To correct the problem, Ford recommends the installation of a kit (Ford part number E92Z-010344-D) to replace the original crankshaft pulley, alternator pulley and accessory drive belt with ones which will permit the alternator to turn at higher shaft speeds.

FORD 1993-1994 Ranger
Ford Technical Service Bulletin # 94-18-8 warns that some 1993-1994 Rangers may experience a state of low battery charge due to belt slippage in wet conditions. It suggests that an additional splash shield (Ford part number F47Z-14A411-A) be installed on the left-hand fender apron to prevent road splash from reaching the belt.

FORD 1993-1994 Ranger 3.0L
1993-1994 Ford Rangers with the 3.0L engine may experience a slow-crank or no-start condition due to a discharged battery. The heater fan switch being left in the "on" position when the engine is shut off and the key removed can cause this condition. Under these circumstances the voltage regulator continues to energize the alternator, gradually draining the battery. To correct this problem, Ford has developed a jumper harness kit (Ford part number F47-14A411-4) which, when installed in the fuse box, prevents the alternator from being energized with the ignition off. Installation instructions are included with the kit. Failure to correct the problem will impose a strain on the charging system, which can lead to failure of the alternator, battery or even the starter.

FORD 1992-1993 Taurus, Sable V-6
1992-1993 Ford Taurus and Sables with V-6 engines may experience a slow-cranking or no-start condition even after the battery, alternator and starter have been replaced. If the condition persists although the charging system works to specs, the problem may be a short circuit in the 12A581 and 14290 wiring harness. These harnesses run across the edge of the transmission case. Over time, the sharp edge may cut into the wires, causing them to short to ground or to each other, causing the no-start condition. Examine these wires for evidence of chafing or abrasion and repair as required. Reinstall a protective covering around them and secure them away from the edge.

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GM All 1994 and later with CS130D
The CS130D series of alternators introduced by General Motors in 1994 has a unique feature, which makes it more difficult to diagnose than previous series. Built into the regulator of the CS130D is a temperature sensor whose function is to shut down the alternator whenever its internal temperature exceeds 280 F. When this occurs, the unit's output drops to zero and the dash warning light is lit. The alternator will resume charging again once its temperature drops below 280 F. Drivers whose vehicles are subject to long periods of idling under heavy electrical loads in hot climates may notice the intermittent dash light and complain that their alternator is failing. In fact, the alternator may be working exactly as it was designed to do.

GM 1990-1995 Buick, Chevrolet, Oldsmobile, Pontiac 3.1L; 3.4L
Many 1990-1995 GM cars with the 3.1L and 3.4L engine may develop an intermittent no-start condition where turning the key produces only a click. If a thorough check of the starting and charging system finds no other problems, check to see if an aftermarket antitheft system has been installed. It has been found that some aftermarket antitheft systems, including the "Goodwrench" system, may add enough resistance to the starting circuit to prevent the solenoid from working properly. Rewiring the solenoid circuit with heavier gauge wire usually eliminates the problem.

GM 1992-1995 Lumina APV Silhouettes and TransSports with the 3.8L engine may develop intermittent drivability problems, which may be accompanied by erratic instrument cluster operation and fluctuating charging rates. The appearance of these problems may be followed by alternator failure, but the problems may persist even after the alternator is replaced. General Motors has determined that t the problem can be caused by a poor ground at the G105 stud location, on the right side of the engine just behind the serpentine belt, under the front coil of the DIS coil pack. The nut securing the ground wires to the stud may be loose. Cleaning the stud and re-torque the nut to 17Nm (12 ft. lbs) will correct the problem.

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