|
I can’t help with the AutoPilot but I’m aware that the dimmable instrument panel illumination lights are fed from the INST blade on the headlight switch, to and through the INST fuse on the fuse block and thence to a junction that feeds the LH & RH dash light bulbs (two bulbs, each side) plus the dimmable lights in the radio, clock & heater-A/C switch (combined), and the shifter display at the console. I’m sure you are aware that the intensity of all these bulbs is controlled by twisting the headlight knob. Twisting the knob with the knob pulled out one or two notches should cause all of the dimmable bulbs to change intensity equally. If none of the dimmable bulbs changes intensity, the problem is probably in the headlight switch. It has a circular variable resistor that may not be functioning properly. The first thing to check is the system Voltage. The system Voltage should be 13.3-14.3 with the engine running. Low Voltage may also be affecting your AutoPilot and would be noticeable at headlights, courtesy lights, stop, tail park & brake lights and trunk light. I’d also suggest checking the fuse block to see if there is corrosion at the clips that hold the INST fuse. All told, there are nine bulbs on the instrument panel. Dimmable: Four: Panel illumination & One: heater/clock. Additional dimmable bulbs include the shift panel on the console and the radio, Non-dimmable: High beam, L&R turn signal and low oil pressure. All receive their ground through the pot-metal instrument panel casting. Eight of the bulbs are held in twist-in plastic holders with brush electric contacts to the circuit board. If all nine bulbs are working at all, the problem is probably not a cracked circuit board. There are two five-socket connectors that fit over round brass pins on the two printed-circuit boards. The pins are connected to the circuit boards like a rivet with a crimp on the back of the circuit board. A flanged foot is then pressed into contact against a copper strip on the PC board. I have noted several times that this crimp can become loose enough to break contact with the circuit board. A little tapping on the back tightened up this mechanical (not soldered) electrical joint. I think it unlikely that the two illumination bulbs on each side of the panel would yield poor connectivity at the same time as they are fed from separate five-pin connectors. If the high-beam, low oil-pressure and turn-signal bulbs burn brightly, the problem would not be a bad ground. Further, when the headlight switch knob is twisted to the far left, the courtesy lamps should come on at full intensity with the doors closed and with the knob pulled out one or two notches. At hat point. the dimmable bulbs should be at their brightest as their feed current is not flowing through the resistor. I have about 1 Ohm between B2 and INST at full left. When the knob is twisted, the variable resistance runs from about 5 Ohms at far left to 9 Ohms near the far right. Twisting the knob to the far right will open the circuit and shut off all dimmable lights. Brightest dimmable lights will be just before the switch knob is turned to the far right. Excessive resistance in the switch at this point is possible due to oxidized internal contacts, will limit the brightness of all dimmable lights and signify the need to replace the headlight switch.. They are readily available. Summary:
I hope this helps. It helps me to review this stuff. Let there be light. Rich Barber Brentwood, CA From: Chrysler300@xxxxxxxxxxxxxxx <Chrysler300@xxxxxxxxxxxxxxx> On Behalf Of Harry Torgeson torg66@xxxxxxxxx [Chrysler300] My auto pilot makes a noise like a fan with the ignition turned on, my mechanic disconnected it, anyone one else have had this happen? my instrument lights are dim, mechanic says its the circuit board, can this be fixed? Thanks Harry __._,_.___ Posted by: "Rich Barber" <c300@xxxxxxx> To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to https://groups.yahoo.com/neo/groups/all/manage/edit For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylang __,_._,___ |
Back to the Home of the Forward Look Network
Archive Sitemap