How to Repair Brake Pedal Position Sensor or Engine service

[Pivo]

Hi there,
I decided to take the position sensor off: it is constantly giving me trouble.
I cannot figure out for the life of me how to unclip the damn clip that retains it.
One member says:
"I had a time with removing the sensor as well. There is a cir-clip that locks the unit in. The lock for the clip is on the master cylinder side.Lift it off of the lock."
Lift off the clip? how? where? what "lock"? I see there is a sorta slot at 3:00: I insert small screwdriver there, does nothing.
I just don't understand how this works... help!
Pierre

[ThommyKent]

That slot at 3:00 is were the clip clicks into the sensor. It`s kind of tricky to get the clip off, but slide a very thin screwdriver underneath to pick up one of the ends then get another underneath the clip, work it around and the clip should snap off. The new sensor comes with a new clip so no worry if it goes flying which it probably will. To put the new sensor in, first install the clip with the open end at 9:00 to 12:00. The sensor has a notch on it at 3;00 to match up with the housing. You need to push and wiggle until you feel the clip click. It`s not a real tight fit, but you will know it`s in if you can`t pull it out.

[mrbrian200]

You don't have to break the sensor open and make a mess. Note the actuator rod is off center. Hold rod in and drill two small holes in the end centered above and below the actuator rod (see pic), just deep enough to get to the inside (don't insert the drill bit/dremel in any further than necessary to create holes. Fill with CRC electronic cleaner or MAF cleaner from the small side (Hole #1 on the picture). press/release the actuator rod quickly 20-30 times. Turn upside down to drain. Blow out with compressed air. Repeat if you feel necessary. I filled/emptied mine 2 or three times. Unless your problem is bad solder joints this fixed it for me. Depressing the actuator rod while drilling is necessary otherwise you may damage the sweep. Spraying in hole #1 specifically hits the sweep and the contact areas on the board. I should not be necessary to plug the holes--the assembly is not sealed on the booster side anyway (no o-ring or seal around the actuator rod).
Oddly if somebody else had not previously torn one apart and posted pictures so that I could see what was inside I would not have figured this out.

[mrbrian200]

Mine started acting up again after a couple months. Replaced with a new one. Per my inclination I tore the old one apart and found some of the potentiometer resistive material had flaked off the copper board traces at the 'brake off' position. Diag code description in VIDA said something to the effect 'sensor reading impossible'.

[br0dy519]

You don't have to break the sensor open and make a mess. Note the actuator rod is off center. Hold rod in and drill two small holes in the end centered above and below the actuator rod (see pic), just deep enough to get to the inside (don't insert the drill bit/dremel in any further than necessary to create holes. Fill with CRC electronic cleaner or MAF cleaner from the small side (Hole #1 on the picture). press/release the actuator rod quickly 20-30 times. Turn upside down to drain. Blow out with compressed air. Repeat if you feel necessary. I filled/emptied mine 2 or three times. Unless your problem is bad solder joints this fixed it for me. Depressing the actuator rod while drilling is necessary otherwise you may damage the sweep. Spraying in hole #1 specifically hits the sweep and the contact areas on the board. I should not be necessary to plug the holes--the assembly is not sealed on the booster side anyway (no o-ring or seal around the actuator rod).
Oddly if somebody else had not previously torn one apart and posted pictures so that I could see what was inside I would not have figured this out.

Got an ECM-9400 today in VIDA. I'm going to try this. Thank you very much for posting this, it may save many of us $150CDN.