Chrysler Repair: 2000 CHRYSLER T&C VAN BLOWING FUSE #12, amp fuse, rear defogger


Question
QUESTION: ROLAND,
  I RATED YOU. THE FUSE THAT KEEPS BLOWING IS UNDER DASH ON DRIVERSIDE ALL THE WAY OVER TO THE RIGHT ITS A 10 AMP FUSE.IT BLOWS WHEN EVER I MOVE GEAR SHIFTER. AND IT DOES ALSO CONTROL A/C CABIN BLOWER. JUST IN CASE YOU FORGOT:2000 CHRYSLER TOWN & COUNTRY LXi

ANSWER: Hi John,
That is very helpful to me, as I now am certain that the '98 diagrams are good through to the '00 model year.
That is fuse 12 and it does a number of different things, as you suggested. Is your vehicle one that has a daytime running lamp module? That is also powered off #12 for the flasher purpose which would explain why the turn signals go out when the fuse blows. It also powers the abs and the front blower motor relay, and the rear defogger relay. And do you have All-wheel drive?
If so, I suspect that if it blows when you put the vehicle in reverse then it has to do with a circuit that takes the current from the #12 fuse and sends it to the transmission range sensor at the transmission itself where when you put it in reverse it is then connected to operate the all-wheel drive solenoids which are located in front of the gas tank, under the vehicle. It appears to be split in to two plugs, 2-wire plugs, each plug has a violet/white 'hot wire' when you put it into reverse which goes into the solenoid and a black wire that comes out of the solenoid and to a near-by ground on the body at the bottom of the left tail light assembly. You could try pulling the to gray plugs and see if that prevents the fuse from blowing, and if not, check the violet/white to see if it is shorted to ground when the fuse is removed from the socket and the plugs are removed from the solenoids. (It it does stop blowing than there is something wrong with the solenoids themselves.) If it is shorted then you will have to trace that wire back to the transmission. It goes through 3 connectors along the way so we can segment the search to find where it is shorted. Please let me know of progress.
Roland
PS: Now that I am open to 'rating'...please feel free to do it again. And thank you for the very nice compliment.

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QUESTION: ROLAND,
  I DON'T HAVE DAYTIME RUNNING LIGHTS AND MY VAN IS A 2WD.

ANSWER: But does the fuse blow when you put it in reverse, nonetheless? Or is there any other clue as to what makes it blow? If none, then we have to disconnect all those circuits on that fuse (by pulling plugs and testing) in order to find out why.
Roland

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QUESTION: THE FUSE BLOWS WHEN I PUT IT IN ANY GEAR.I CHECKED THE REVERSE LIGHT BULBS, THEY ARE OK.IF I GO STRAIGHT TO DRIVE AND BYPASS REVERSE IT STILL BLOWS FUSE.THATS THE ONLY TIME THE FUSE WILL BLOW IS WHEN THE GEAR SHIFTER IS MOVED.

Answer
Hi John,
There could be a wiring difference between what is in your '00 and what is shown in my '98 and '02 manuals. One unknown, to me, is whether you have a 3-speed non-electronic automatic or a 4-speed electronic automatic. On the former, the only thing that the #12 fuse is used for with regard to the shift lever is to power the back-up lamps via the switch on the transmission. On the 4-speed it is only used for the solenoids associated with 4 wheel drive which you don't have so in theory there shouldn't be a white wire from the fuse that goes to pin 1 of the range sensor or it there was it would not be connected to an ouput wire on pin 6 that is violet black in color because that would be going to the solenoids that aren't installed. I would suggest that you go to the transmission and look at the vertical rod which rotates when a helper in the cabin moves the gear shift lever. If this is the electronic trans, which I would believe is used in the T&C, if you look at the base of that lever you should find an 8-pin plug. If there is a  white wire on pin 1 then unplug the plug and measure for 12v on the pin when you turn the ignition 'on'. If there is, then the question is what is the wire color on pin 6  (violet/black) and if so what is the resistance to ground shown by that pin with the plug removed from the range sensor socket. If it is a dead short to ground then we have to figure out why and ideally figure out where that wire goes. The other test, if there is 12v on the pin 1 wire, is to measure and cofirm that pin 1 of the socket connects to pin 6 of the socked when you are in R or OD, but not in P or in N.
That is my best suggestion based on my limitations and your observation that in P or N the fuse doesn't blow, but if you shift to R from P it blows, or if you shift from N to OD it blows, correct?
Roland