So my wife's Merc Mountaineers temp and compass display went black after I had just replaced all the O2 sensors for her. She said it had to be my fault. We all know they are not related to each other but wife's who don't know the difference between a crankcase and a suitcase think it's all the same.
I checked the fuses still no display. The owners manual shows the Temp/Compass are on the same loop/fuse as the map lights and rear heater blower. They all worked fine but the display was still out. Knowing something else must be bad and not very enthused to buy a new one or hope one worked from a wrecking yard was good, I decided to research on the net for an answer. Well after looking online I found out its very common for it to fail due to a bad solder connection on the circuit board to a 510 resistor.
The photos below are from the site I found instructions on to show the board and resistors. I forgot to take photos when repairing mine.
I pulled down the overhead console. This was simple two Phillips screws at the rear under the garage door opener door. Next pull the front down and the two clips will release the console. Disconnect the power wire clip to the console. I then removed the map lights and temp/compass display. This was held in by 7 torx screws. Two hide under the foam strips
http://members.rennlist.com/jptl/fix5.jpg
On the temp/compass display part you'll need to remove the black cover to expose the green circuit board. Look in front of the display and there should be two 510 resistors that prone to fail at the connections. These are only about a 1/4" x 1/8". There are other 510 resistors on some boards as well but it's the two in front of the display that seems prone to fail.
http://www.ford-trucks.com/forums/picture.php?albumid=6604&pictureid=25269 http://www.ford-trucks.com/forums/m...keith's+album-6604-picture-img-0003-25269.jpg
Next inspect for bad connections at the end of the resistors and the board. Most failed connections will show a dull grey instead of the bright look of solder. This picture is from the instructions I found on line. My connections are a lot cleaner but you can see where they fail very easily from the photo. For best results solder with a silver base solder but regular flux base will work fine. Since it's such a small connection get the solder to stick to the soldering iron first then attach via soldering the resistor to the circuit board. Check your work by reconnecting the display to the power lead clip. Push the mode button a few times. It should light up and work if your solder connection/s are good if not solder again and retest the display.
http://www.ford-trucks.com/forums/picture.php?albumid=6604&pictureid=25270
This is how mine looked after connecting just one bad solder connection on the two 510 resistors. The display lives on.
http://www.therangerstation.com/Magazine/Fall2008/overhead_console/overhead_console.JPG
I hope this helps someone get theirs working again.
I checked the fuses still no display. The owners manual shows the Temp/Compass are on the same loop/fuse as the map lights and rear heater blower. They all worked fine but the display was still out. Knowing something else must be bad and not very enthused to buy a new one or hope one worked from a wrecking yard was good, I decided to research on the net for an answer. Well after looking online I found out its very common for it to fail due to a bad solder connection on the circuit board to a 510 resistor.
The photos below are from the site I found instructions on to show the board and resistors. I forgot to take photos when repairing mine.
I pulled down the overhead console. This was simple two Phillips screws at the rear under the garage door opener door. Next pull the front down and the two clips will release the console. Disconnect the power wire clip to the console. I then removed the map lights and temp/compass display. This was held in by 7 torx screws. Two hide under the foam strips
http://members.rennlist.com/jptl/fix5.jpg
On the temp/compass display part you'll need to remove the black cover to expose the green circuit board. Look in front of the display and there should be two 510 resistors that prone to fail at the connections. These are only about a 1/4" x 1/8". There are other 510 resistors on some boards as well but it's the two in front of the display that seems prone to fail.
http://www.ford-trucks.com/forums/picture.php?albumid=6604&pictureid=25269 http://www.ford-trucks.com/forums/m...keith's+album-6604-picture-img-0003-25269.jpg
Next inspect for bad connections at the end of the resistors and the board. Most failed connections will show a dull grey instead of the bright look of solder. This picture is from the instructions I found on line. My connections are a lot cleaner but you can see where they fail very easily from the photo. For best results solder with a silver base solder but regular flux base will work fine. Since it's such a small connection get the solder to stick to the soldering iron first then attach via soldering the resistor to the circuit board. Check your work by reconnecting the display to the power lead clip. Push the mode button a few times. It should light up and work if your solder connection/s are good if not solder again and retest the display.
http://www.ford-trucks.com/forums/picture.php?albumid=6604&pictureid=25270
This is how mine looked after connecting just one bad solder connection on the two 510 resistors. The display lives on.
http://www.therangerstation.com/Magazine/Fall2008/overhead_console/overhead_console.JPG
I hope this helps someone get theirs working again.
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