2000 JGC / Windshield Wiper low-fluid alarm

Try cleaning the connector and making sure the little floaty thing is floating and not stuck.

"DougW" wrote

Try cleaning the connector and making sure the little floaty thing is floating and not stuck.

On Thu, 25 Dec 2008 09:28:12 -0600, "DougW" wrote:

*************** As my reservoir appears to be blow-molded, the electrical bits are not integral and it looks like they should be replaceable separately. I haven't check with my friendly Mopar parts guy to see it the sensor is sold separately. Reading below, it doesn't look like it can be calibrated, it works or it doesn't and if not functioning, replace it.

Here's a cut / paste from the factory service manual, I'll a copy of the JPEGs in alt.binaries.pictures.auto.4x4

reboot

From the WJ FSM ...

Description The washer fluid level switch is a single pole, single throw reed-type switch mounted near the front of the washer reservoir, forward of the two washer pump/motors (Fig. 17). 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.

OPERATION 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 is connected to the vehicle electrical system through a dedicated take out and connector of the left headlamp and dash wire harness. The switch receives a five volt reference signal from the Body Control Module (BCM) through the washer fluid switch output circuit. The switch is grounded at all times through another take out of the left headlamp and dash wire harness with a single eyelet terminal connector that is secured under a ground screw near the top of the left front fender inner shield in the engine compartment. When the switch closes, the BCM senses the voltage change on the circuit. The BCM is programmed to send low washer fluid messages to the Electronic Vehicle Information Center (EVIC) over the Programmable Communications Interface (PCI) data bus. The EVIC is programmed to respond to this message by displaying the Washer Fluid Low warning and sending a chime request message back to the BCM over the PCI data bus. Then the BCM generates an audible chime tone warning. A resistor within the washer fluid level switch allows the BCM to monitor and diagnose this circuit. The BCM will store a Diagnostic Trouble Code (DTC) for any fault that it detects. For retrieval of this fault information and further diagnosis of the washer fluid level switch, the BCM, the EVIC, the PCI data bus, the BCM message outputs to the EVIC that control the Low Washer Fluid indicator, or the EVIC message outputs to the BCM that control chime service, a DRBIIIt scan tool and the appropriate diagnostic information are required.

REMOVAL The washer fluid level switch can be removed from the washer reservoir without removing the reservoir from the vehicle.

(1) Disconnect and isolate the battery negative cable.

(2) Remove the one screw that secures the washer reservoir filler neck to the left inner fender shield.

(3) Raise and support the vehicle.

(4) Remove the liner from the left front fender wheel house.

(5) Disconnect the washer hose from the barbed outlet nipple of the rearmost (front) washer pump/ motor unit and allow the washer fluid to drain into a clean container for reuse.

(6) Remove the two screws that secure the inboard mounting flange of the washer reservoir to the left inner wheel house.

(7) Pull the bottom of the washer reservoir rearward far enough to access the left headlamp and dash wire harness connector for the washer fluid level switch on the front of the reservoir

(8) Disconnect the left headlamp and dash wire harness connector for the washer fluid level switch from the switch connector receptacle.

(9) Using a trim stick or another suitable wide flat-bladed tool, gently pry the barbed nipple of the washer fluid level switch out of the rubber grommet seal on the front of the reservoir (Fig. 18). Care must be taken not to damage the reservoir.

(10) Remove the washer fluid level switch and float from the washer reservoir.

(11) Remove the rubber grommet seal from the washer fluid level switch mounting hole in the washer reservoir and discard.

INSTALLATION

(1) Install a new rubber grommet seal into the washer fluid level switch mounting hole in the front of the washer reservoir. Always use a new rubber grommet seal on the reservoir.

(2) Position the float of the washer fluid level switch through the rubber grommet seal in the washer reservoir (Fig. 18). The connector receptacle of the washer fluid level sensor should be pointed downward.

(3) Press firmly and evenly on the washer fluid level switch until the barbed nipple is fully seated in the rubber grommet seal in the washer reservoir mounting hole.

(4) Reconnect the left headlamp and dash wire harness connector for the washer fluid level switch to the switch connector receptacle.

(5) Reconnect the washer hose to the barbed outlet nipple of the front washer pump/motor unit.

(6) Install and tighten the two screws that secure the inboard mounting flange of the washer reservoir to the left inner wheel house. Tighten the screws to

7.4 N·m (66 in. lbs.).

(7) Reinstall the liner into the left front fender wheel house.

(8) Lower the vehicle.

(9) Install and tighten the one screw that secures the washer reservoir filler neck to the left inner fender shield. Tighten the screw to 7.4 N·m (66 in. lbs.).

(10) Fill the washer reservoir with the washer fluid drained from the reservoir during the removal procedure.

(11) Reconnect the battery negative cable.

Thanks a lot reboot !!!

James

Interesting. I thought mine was a reed switch, but the service manual says it's a resistor. That doesn't make sense for that type of sensor. That would place it in the same category as the fuel sensor. A float and a rod or some sort of commutator. Now mine is a ZJ, but reed switches usually don't fail and if they do it's in the stuck mode from an overly powerful magnet. If the relay closes when the float is on Empty then an open or bad connector would not cause that problem. If the float was stuck, that could cause the problem.

Got me. If disconnecting the sensor stops the error that would be what I'd do. Just keep an eye on the fluid from that point on till you can get a new one.

Check here for the part. That's a dealer but without the $$$$ overhead charges.

Thanks Doug !! Yes, I am going to try to disconnect the sensor today, and see if that stops the error. And, the Chrysler Parts Direct side would be a good source for the part.

Thanks again !!

James

What's that Lassie? You say that DougW fell down the old rec.autos.makers.jeep+willys mine and will die if we don't mount a rescue by Thu, 25 Dec 2008 21:09:25 -0600:

it's a resistor.

It's a reed switch AND a resistor. The resistor is across the switch, so the computer can detect a wiring fault/unpluged connecter.

The computer should: sense the resistor when bottle is full, sense a closed connection when low, sense a open connection if unplugged/busted wire.

That makes more sense. Same as similar magnetic switches used for security sytems.

Wonder why the service manual doesn't show the switch and resistor. Guess they were just lazy.

What's that Lassie? You say that DougW fell down the old rec.autos.makers.jeep+willys mine and will die if we don't mount a rescue by Sat, 3 Jan 2009 20:50:04 -0600:

They probably show just the combined unit, as it would have to be replaced as one piece. But it would be nice to know about for when your trying to pin down a fault.