Safari and Astro Van

SAFARI AND ASTRO VAN




^ Short to ground in VSS sensor circuit 821 or 822, on all wheel drive versions. The problem is usually at the transfer case where the wiring harness is routed over the top. The harness generally rubs through on one of the flanges of the transfer case (figure 1).

^ Short to ground in circuit 821 or 822 at the wiring clamp, behind the exhaust shield.

^ Circuits 821 or 822 shorted at the engine cover bracket or valve cover.




^ Water intrusion into the PCM connector C-240, causing terminal corrosion. Connector C-240 is mounted under the passenger side of the dash, next to the PCM (figure 2). Water intrusion into this area is usually due to a windshield leak in the right corner of the dash.

Circuit 420 (TCC) of the main harness is shorted to ground on the right-hand side of the engine (the wire rubs through on the engine cover bracket). This condition will also result in the transmission going to default mode, and will greatly affect other vehicle systems. Other systems affected will include: the shift interlock solenoid, speedometer and ABS... all of which will be inoperative since the problem will cause the brake fuse to fail, which is used to feed all of these systems.

^ A loose or damaged toothed-wheel on the output shaft which is used for the VSS.

^ Poor connection at terminal J or G in connector C-240. If the connector is not fully latched, ABS code 37 may set in conjunction with code 72.










^ A loose or corroded battery ground bolt. This problem is generally ground G-102 (figure 3A) which is mounted under the water pump/ power steering pump area of the block, or G-150 (figure 3B) which is mounted to the radiator core support. If these grounds are not corroded or loose, inspect ground G-197 (figure 3C) for a possible problem. A problem with G-150 may also cause the dash lamps to be dim.

^ Extension housing or output shaft bushing loose.

^ The vehicle speed sensor circuits are routed with the main vehicle harness. This harness travels along the bellhousing and enters the cab on the passenger side. If the harness is too close to any spark plug wires, a code 72 will result due to EMI. Reroute the plug wires away from the P-100 (pass through connector) area (figure 2).

^ Loss of battery voltage to the bulkhead connector. (The bulkhead connector is located on the driver's side, close to the brake booster.)