20 Most Recent 2003 Mercury Mountaineer Questions & Answers

It could be a bad temperature sensor producing a false warning. Also, check the oil....sometimes low oil levels could cause the overheat light to come on. Next, have it check out by a mechanic

2003 Mercury... | Answered on Jan 03, 2020

bad door switch. See this post


The BCM sees it as a door opening and sets off the alarm

A bad door switch can malfunction ANY time. The alarm is looking for a door switch or hood switch opening. That's where you start--with an intermittent switch

2003 Mercury... | Answered on May 14, 2019

go to your local parts store and buy a can of PB BLASTER lubricant then open each door and spray the latch assembley really good then close and open the door 10 to 15 times. do this with each door. the door ajar light switch is located in the door latch assembley and cannot be seen so soak the latch assembleys really good so lube reaches the switch. these switches sometimes get stuck but this usually frees up the switch

2003 Mercury... | Answered on Mar 12, 2019

Try resetting the alarm, using the instructions given at the link below. I'll also copy the text here.

  1. Insert the ignition/door key in the door lock on the driver's- side door of your Mountaineer.
  2. Turn the key to the lock position.
  3. Turn your key to the unlock position.
  4. Turn your key to the lock position.
  5. Turn your key to the unlock position. Your alarm is now disabled. If your key fob works, you can also press the unlock or alarm-disable button on the fob.
  6. Start the Mountaineer's engine and allow the vehicle to run for at least 10 minutes. This will allow the alarm to relearn the default settings. You must make sure that you have disabled the alarm first, however, before you attempt to start the vehicle, so that the alarm will reset itself.

If these instructions don't work, you can try resetting the car's computer by unplugging the battery for half an hour. However, that will reset the keyless entry code, as you can see in the fixya article I link to at the bottom


2003 Mercury... | Answered on Mar 06, 2019

Your Service Engine Soon light has nothing to do with reminding you to change your oil. The light is controlled by the ECM (Computer) in your vehicle. It monitors various sensors in your engine and compares them to variables or programs that is in its memory. When something is not registering correctly or is outside of its parameters it will turn on a MIL(Malfunction Indicator Light)or in your case a Service Engine Soon light. You will need a OBD II ( On Board Diagnostic) reader or scanner to hook up to your diagnostic port under your driver's side footwell to read what code the ECM is putting out. Than with the code the mechanic can look up the code to see what part is sending a malfunctioning. The scanner can also read and erase the code too. You can have your code pulled up with a OBD II scanner for free from any AutoZone store.

2003 Mercury... | Answered on Feb 27, 2019

Front:? Axle half shaft needs replacing.

2003 Mercury... | Answered on Sep 23, 2018

1. Raise the vehicle so you can safely get underneath. The starter is typically located under the engine near the transmission mating surface. DON'T RELY ON A CHEAP JACK! Use drive on ramps or jack stands safely positioned on the frame, and lock the parking brake AND chock the rear wheels to keep it from rolling.
2. Disconnect the negative cable from the battery to remove voltage from the system. Don't want to arc yourself to the frame when you disconnect the cables from the starter!
3. Locate the starter motor and remove the nut that holds the starter cable in place, remove the cable and position it out of the way.
4. Disconnect the solenoid connector...the smaller of the two wires going to the starter.
5. Remove the bolts holding the starter to the mount...usually 2, sometimes 3.
6. Remove the old starter.
7. Carefully compare the old to the new...make sure they match.
8. Install the new starter...thread all the mounting bolts in hand tight, then torque them to the specification listed in the service manual.
9. Reconnect the two wires you removed earlier.
10. Reconnect the battery.
That should do it! Hope this helps...

2003 Mercury... | Answered on Jul 06, 2018

My personal suggestion would be to go for these repair catalogs from www.reliable-store.com instead.
much better info on all vehicles, complete details, and they also have live assistance feature

2003 Mercury... | Answered on Mar 08, 2018

Try this article. It explains some of the internals of your transmission. HOPE THIS HELPS? FORD "FOUR VERSIONS OF 5R55"
FORD "FOUR VERSIONS OF 5R55" Just as the title states, the Ford 5R55 Transmission has four versions. Ford 5R55 can have an N, S, or W behind those numbers.
  • The 5R55 is a rear wheel drive 5-speed that appeared in 1999 and later vehicles.
  • The 5R55W came out in the 2002 and later Ford Explorer and Ford Ranger models.
  • The 5R55N appeared in the Jaguar S-Type and Lincoln LS and in 2002 in the Ford Thunderbird.
  • The 5R55S without the Select Shift is used in the 2005 and later models of the ford Mustang.In 2003 the Thunderbird and Lincolns switched to the 5R55S that had the Select Shift (allows drivers to shift like a standard without the clutch).
Although the 5R55N is very similar to the W or S models, only a few parts are interchangeable.
We receive numerous calls about these where someone has rebuilt the transmission, yet still experiences the same symptoms. The most common problem we see on these units is the excess wear on the case or valve body.
Transmission case premature wear occurs on the overdrive and intermediate servo bores. Apply oil comes up through the servo pin bore and through the hollow pin applying the servo. This requires the pin to seal in the servo pin bore, as well as the release oil that both servos require. Over time, the number of apply and release wears out and the pin can no longer seal properly. The overdrive servo bore will usually have more wear due to it being used for second and fifth gear. As the servo leaks, which will result in a pressure loss, it lacks the pressure to hold the band completely applied or release it fast enough to prevent the band from being burned up.
These issues can be repaired without replacing the case. Drilling the servo bores and installing a "cesleeve" to compensate for the wear eliminates the need to replace the case. The brass sleeve has proven to be more durable then the aluminum case, giving you more stability. You don't want to use a "used case" as the possibility of the bores being worn in is very likely.
The valve body can also have excessive wear, most often seen on the TCC (torque converter clutch) modulator bore, or main regulator bore. In this case, the high duty cycle of use wears down the bore reducing clutch and servo pressures. Although the PCM (power control module) will try to compensate with an adaptive strategy, the excess wear will cause gear ratio or slipping codes.A valve body repair or update kit will usually correct these problems.
Gear ratio error codes are very common on these transmissions due to servo pin bore wear occurring at a very low mileage, in some cases.You can have a gear ratio error code without having an electrical code (solenoid), but it is unlikely that you will have an electrical circuit code without a gear ratio error code.
These are just a couple of most common problems seen on these transmissions, but not all these problems may have this problem. If you have any version of the Ford 5R55 transmission and are having problems with it, don't hesitate to bring your vehicle into The Transmission Shop to get it checked out. Having a proper diagnostic by qualified techs will eliminate the guess work and save you major expenses in the repair, rebuilding, or replacement of these transmissions.

2003 Mercury... | Answered on Feb 10, 2018

What are the DTC'S - diagnostic trouble code's ?

2003 Mercury... | Answered on Jan 13, 2018

get a new mechanic
ether a break has locked up or a gear is locking up you need to get this looked at before you do thousands of dollers of damadge

2003 Mercury... | Answered on Nov 09, 2017

The rear blend door opens and closes to regulate air temperature. It's operated by a small electric motor. So the problem can be a stuck door, bad linkage (if your model uses linkage) or a bad motor. Bad motor is most common failure, but they usually fail in one position, not the clicking state. You'll have to remove the trim panel from the rear heater assembly. Then just follow the wires to a flat black box and listen for the noise. That'll be the actuator. Disconnect the electrical connector. Remove the screws that hold it in place. Then try moving the door by hand. If it moves freely, then the actuator is bad. Replace it.

2003 Mercury... | Answered on Oct 28, 2017

it could be the universal joints on the drive shaft going bad

2003 Mercury... | Answered on Oct 14, 2017

if it has a viscous fan hub --replace it
if it has electric fans , check/ replace the coolant temperature sensor , fan relays or fan motors
have a compression test done to check for gasket or cracked head/s
over heating once a week is not constant so have the fault codes read to check for heated oxygen sensor problems altering the air / fuel mixture

2003 Mercury... | Answered on Oct 04, 2017

O/D light flashing is telling there is a problem with the transmission an trouble codes are stored . The clicking you hear in the rear climate control system is mode door or blend door actuator . There is no accumulator in the rear A/C system . If the A/C system had a accumulator it would be in the engine compartment . Your best bet ,take it to a qualified repair shop.

2003 Mercury... | Answered on Jul 13, 2017

Have the engine cooling fan operation checked, it may be defective and that can cause the noise.

2003 Mercury... | Answered on Jul 05, 2017

Did you check all aspects of new one and old one, all it takes is one thing not same and cause problems, depth of threads and nut? diameter ? angle of flare? sounds like ya got the wrong hose though.

2003 Mercury... | Answered on May 24, 2017

On just one specific cylinder or multiple cylinders ?

2003 Mercury... | Answered on Apr 11, 2017

Assuming it is w/o IVD, 15A FUSE 23 and 10A fuse 22 in the central junction box plus 40A FUSE 5, 30A FUSE 10, and 2A FUSE 45 apply.

2003 Mercury... | Answered on Feb 07, 2017

I would say the key thing has nothing to do with the window going back up . If it were a power problem , it would affect all windows . They all get B+ voltage from the accessory delay relay , located in the central junction box,under dash panel, LH side .Which switch are you using , driver or the switch at that door . or does it make a difference ? Do you know how to do electrical testing . I would say it's a switch or motor problem for that window . Automotive Electric Window and Switch Troubleshooting Repair Guide

2003 Mercury... | Answered on Jan 30, 2017

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