Marquis fuse #13 blows only when put in gear
 

Hello

My 99 Mercury Marquis keeps blowing fuse #13 but only when put into gear don't matter which gear. When this fuse is blown I have no gauges (fuel, batt, speedo, oil pressure, etc...) I thought maybe my speed sensor was bad so I replaced it but no luck. Also the trans shifts hard I bought a transmission control solenoid but not installed yet.

Any suggestions as to what could cause fuse #13 to blow when put into a gear would be very helpful.

sounds ike there's a wiring issue in the column. You may need to take the column covers off and look for wires that rub against the shifter. There may also be a short in whatever sensor detects the shifter position for the dash display if it's not a mechanical cable lik the ones I'm used to. This sensor may be on the transmission if equipped (I'm not sure if they offered digital dashes like that in later models - last one I saw was on a 94 I think). I had the same issue with my 88 and the E-Brake crushing an unused cornering light wire harness. It would short and blow the fuse. Had to wrap it with electrical tape and tuck it out of the way.

Hopefully this helps.

Short
 

Thanks for your reply slymer it was a short with the O/D switch on the gear shifter. I disconnected the wire for now and will order a new gear shifter when I have the money.

Trans is still shifting hard in the owners manual it says fuse 13 also powers electronic transmission but doesn't say what it powers on the trans. Is it possible with that fuse being blown and driving the vehicle could it have damage the electronic transmission any ideas on what I should look into replacing or what to test.

I may have. But it may also just be the trans computer re-learning itself. if the fuse is replaced and keeps working for a few more full temp cycles, it may smooth out. If it doesn't, you may have to get it checked out.

yeah it does seem to be getting smoother

sounds like it may be back to normal by the middle of the week or weekend then. Hope you can get the shifter sorted without much loss in the wallet.

Yeah,overdrive cancel switch is a common issue on the column.
It chafes right where the wire leaves the shifter arm,only fix is replace shifter arm but it's an easy job.

This circuit should be checked ANYTIME you have any kind of electrical issue involving the cluster,ignition,cruise or wiper switch usually.

It is the most common UNCOMMON short I see,it causes everything from PATS transciever failure to cluster failure to funny shifting trans,phantom wipers etc... etc... etc..

It's crazy how much stuff that short can affect,but there are alot of circuits that route through the column (though not necessarily controlled by anything on the column even).

The trans shifting smoothly just needs relearned as slymer said.
But you might see if it's time to flush or change filter,however it shifts after a reset is how it shifts without the computer tuning out any issues.
If it's hard shifting you might trying cleaning your MAF,as it is the main load calculating device for trans shift pressures.
If you run a K&N on a FoMoCo (or anything really)than you should be cleaning your MAF at every oil change.
Don't use brake or carb clean,use electrical contact or MAF sensor cleaner. It's expensive(8$?) but you gotta have it.

Good to know about the MAF cleaner. I have contact cleaner (keep a stock of it with the electronics I play with) and the 93 has a MAF system. Considering it's age, it may be time to hose it out.

Real quick on cleaning the MAF that I should have mentioned.
Just spray the crap out of it with the spray,don't touch it.

Also,have the key turned off,and make sure the vapors and MAF have been dried of all the cleaner.
It will evaporate pretty quickly,just make sure it is dry when the car is started again.

If not it will throw off the maf caclulation and you will blow white smoke(lean) when you start the vehicle for awhile and of course the lean reading will be entered in the vehicles fuel learn process.

Not a big deal but annoying.