Part 3 of 3

FRONT WIPER RELAY
The front wiper relay (or intermittent wipe relay) is located in the Power Distribution Center (PDC) near the battery in the engine compartment. See the fuse and relay layout label affixed to the inside surface of the PDC cover for front wiper relay identification and location. The front wiper relay is a conventional International Standards Organization (ISO) micro relay. Relays conforming to the ISO specifications have common physical dimensions, current capacities, terminal patterns, and terminal functions. The relay is contained within a small, rectangular, molded plastic housing. The relay is connected to all of the required inputs and outputs through its PDC receptacle by five male spade-type terminals that extend from the bottom of the relay base. The ISO designation for each terminal is molded into the base adjacent to the terminal. The ISO terminal designations are as follows:
- 30 (Common Feed) - This terminal is connected to the movable contact point of the relay.
- 85 (Coil Ground) - This terminal is connected to the ground feed side of the relay control coil.
- 86 (Coil Battery) - This terminal is connected to the battery feed side of the relay control coil.
- 87 (Normally Open) - This terminal is connected to the normally open fixed contact point of the relay.
- 87A (Normally Closed) - This terminal is connected to the normally closed fixed contact point of the relay.

The front wiper relay cannot be adjusted or repaired. If the relay is damaged or faulty, it must be replaced.

The front wiper relay (or intermittent wipe relay) is an electromechanical switch that uses a low current input from the Central Timer Module (CTM) to control a high current output to the low speed brush of the front wiper motor. The movable common feed contact point is held against the fixed normally closed contact point by spring pressure. When the relay coil is energized, an electromagnetic field is produced by the coil windings. This electromagnetic field draws the movable relay contact point away from the fixed normally closed contact point, and holds it against the fixed normally open contact point. When the relay coil is de-energized, spring pressure returns the movable contact point back against the fixed normally closed contact point. A resistor or diode is connected in parallel with the relay coil in the relay, and helps to dissipate voltage spikes and electromagnetic interference that can be generated as the electromagnetic field of the relay coil collapses.

The front wiper relay terminals are connected to the vehicle electrical system through a connector receptacle in the Power Distribution Center (PDC). The inputs and outputs of the front wiper relay include:
- The common feed terminal (30) is connected to the front wiper motor low speed brush through the wiper control circuitry of the multi-function switch on the steering column. When the front wiper relay is de-energized, the common feed terminal is connected to the front wiper park switch output through the CTM on the front wiper park switch sense circuit. The front wiper park switch output may be battery current (wipers are not parked), or ground (wipers are parked). When the front wiper relay is energized, the common feed terminal of the relay is connected to battery current from a fuse in the Junction Block (JB) through a fused ignition switch output (run-acc) circuit.
- The coil ground terminal (85) is connected to the relay control output of the CTM through the wiper relay control circuit. The CTM controls the ground path for this circuit internally to energize or de-energize the front wiper relay based upon its programming, inputs from the front wiper and washer control circuitry of the multi-function switch, and inputs from the front wiper motor park switch.
The coil battery terminal (86) is connected to battery current from a fuse in the Junction Block (JB) through a fused ignition switch output (run-acc) circuit whenever the ignition switch is in the ON or Accessory positions.
- The normally open terminal (87) is connected to battery current from a fuse in the Junction Block (JB) through a fused ignition switch output (run-acc) circuit whenever the front wiper relay control coil is energized by the CTM. This circuit provides fused ignition switch output (run-acc) current to the front wiper motor low speed brush only when the front wiper relay control coil is energized.
- The normally closed terminal (87A) is connected to the output of the front wiper motor park switch through the CTM on the front wiper park switch sense circuit. This circuit provides battery current (wipers are not parked) or ground (wipers are parked) to the front wiper motor low speed brush whenever the front wiper relay control coil is de-energized and the OFF position of the front wiper control circuitry within the multi-function switch is selected.

The front wiper relay can be diagnosed using conventional diagnostic tools and methods.

WASHER FLUID LEVEL SWITCH
The washer fluid level switch is a single pole, single throw reed-type switch mounted on the outboard side of the washer reservoir forward of the two washer pump/motors, in the right front corner of the engine compartment. Only the molded plastic switch mounting flange and connector receptacle are visible when the switch is installed in the reservoir. A short nipple formation extends from the inner surface of the switch mounting flange, and a barb on the nipple near the switch mounting flange is press-fit into a rubber grommet seal installed in the mounting hole of the reservoir. A small plastic float pivots on the end of a bracket that extends from the switch nipple formation. Within the float is a small magnet, which actuates the reed switch. The washer fluid level switch cannot be adjusted or repaired. If faulty or damaged, the switch must be replaced.

The washer fluid level switch uses a pivoting, oblong float to monitor the level of the washer fluid in the washer reservoir. The float contains a small magnet. When the float pivots, the changing proximity of its magnetic field will cause the contacts of the small, stationary reed switch to open or close. When the fluid level in the washer reservoir is at or above the float level, the float moves to a vertical position and the switch contacts open. When the fluid level in the washer reservoir falls below the pivoting float, the float moves to a horizontal position and the switch contacts close. The switch contacts are connected in series between ground and the washer fluid switch sense input of the instrument cluster. The switch is connected to the vehicle electrical system through a dedicated take out and connector of the headlamp and dash wire harness. The switch receives ground through another take out of the headlamp and dash wire harness with a single eyelet terminal connector that is secured under a nut to a ground stud located on the right front fender inner shield in the engine compartment. The washer fluid level switch can be diagnosed using conventional diagnostic tools and methods. (Refer to WASHER FLUID INDICATOR - DIAGNOSIS AND TESTING).

Fig. 12 Washer Reservoir:

WASHER RESERVOIR
A single washer fluid reservoir is used for both the front and rear washer systems. The molded plastic washer fluid reservoir is integral to, and located on the right end of the upper radiator shroud in the right front corner of the engine compartment. A bright yellow plastic filler cap with a rubber seal and an International Control and Display Symbol icon for "Windshield Washer" and the text "Washer Fluid Only" molded into it snaps over the open end of the filler neck. The cap hinges on and is secured to a molded-in hook formation on the top of the reservoir just inboard of the filler neck when it is removed for inspecting or adjusting the fluid level in the reservoir. There are separate, dedicated holes on the outboard side of the reservoir provided for the mounting of the front and rear washer/pump motor units and the washer fluid level switch.

The washer reservoir is serviced only as a unit with the upper radiator shroud. The washer reservoir cannot be repaired and, if faulty or damaged, the upper fan shroud unit must be replaced. The grommet seals for the washer pump/motor units and the washer fluid level switch, and the filler cap are each available for service replacement.

The washer fluid reservoir provides a secure, on-vehicle storage location for a large reserve of washer fluid for operation of the front and rear washer systems. The washer reservoir filler neck provides a clearly marked and readily accessible point from which to add washer fluid to the reservoir. The front and rear washer/pump motor units are located in a sump area near the bottom of the reservoir to be certain that washer fluid will be available to the pump as the fluid level in the reservoir becomes depleted. The front washer pump/motor unit is mounted in the lowest position in the sump so that the front washers will operate even after the rear washer system will no longer operate. The washer fluid level switch is mounted just above the sump area of the reservoir so that there will be adequate warning to the vehicle operator that the washer fluid level is low, before the washer system will no longer operate.