Howdy Folks,

I just changed the neutral safety switch, otherwise known as the transmission range sensor, also known as the backup switch by some seasoned hands.


Symptoms of my problem were:

• transmission position readout on odometer screen started getting weird (squares around all the positions, no squares, combinations of the two)
• clicking sounds occasionally behind the dash, sometimes at stops, sometimes driving
• backup lights would not work in reverse, or they would work driving down the road as a postman pointed out to me one day

I did not understand the relationship of the problems until I read my wiring diagram. Once I verified the the reverse light bulbs were OK and I did not have voltage to the bulbs, I felt good that the switch was bad.


The Haynes manual does a great job of describing how to get to the NSS/TRS. It is a little misleading on the actual replacement of the switch though. The steps are as found in Haynes:

• Remove the battery and tray
• Remove the air duct by unscrewing the clamp on the throttle body and unclamping the housing to the air filter
• Drain the engine coolant on the bottom left of the radiator
• Remove the three bolts on the thermostat housing, remove the gasket and thermostat, and then remove the thermostat housing itself. This was the hardest part of the job, the hoses had been stuck on for 9 years and 116,000 miles, and the clamps are tough with pliers.
• Remove the two bolts holding down the NSS, unclip the electrical connector, and pull the switch off.
• Haynes says you have to have a special ford tool to properly align the NSS. This is incorrect, it applies to just about every other car and truck Ford makes if you Google the tool, but not the Escape. The shaft the sensor sits on has 2 keyways making the placement of the new sensor easy. I cleaned up the shaft some and put some dielectric grease on it. Part at NAPA was a Echlin NS5593.

When you put it back together make sure the gasket for the thermostat goes in the right order. The Haynes manual shows an incorrect picture for this with a different looking gasket. Thermostat first with the jiggle valve up at the 1200 position, and then the O-ring. If you reverse it you will have a leak from your thermostat housing and your NSS will malfunction and die, which is how I got to this point from some earlier maintenance!

I put it all back together, put in some new coolant, and it all worked. Backup lights, position on odometer screen, and no more clicking.

Dave