How do I clean my (ECM) Engine Control Module connections.

I am getting code P0112 (intake air sensor low voltage). I changed the sensor with multiple new sensors and the check engine light keeps coming on with the same code "P0112" after the computer has been reset by taking the negative wire off the battery for 5 minutes.

A mechanic said he checked the electrical stuff, and believes it's the computer.

I am going to buy a volt meter and check to see if the sensor is getting 5 volts.

Does anyone know how to clean the connections at the ECM, I have unplugged them multiple times and replugged but that is all I have done.

Purchase some Electrical Contact Cleaner in a spray can. Follow the instructions.

Get a strong light and look inside the connector. You may be able to see some corrosion. You can use a fine emery board to clean the pins on the ECU. Then douse everything real well with some cleaner like Tim said.

Electrical contact cleaner or denatured alcohol (or methanol. Do not use "rubbing alcohol" - it's an alcohol/water solution.)

Apply an old toothbrush as required.

I bought some spray cleaner and followed the directions, I sprayed the connections at the sensor, and the three connections at the computer and the pins.

I also made sure the A.I.T. Sensor was receiving 5 volts with a volt meter, it was.

The check engine light came back on after about 20 miles, around a half hour of driving.

I don't no what to do next, most everything I read is that it is usually not the computer.

The jeep runs great, just that same stupid code that keeps coming back, worst of all they failed me for it even though I passed all the pollution tests, New jersey will not let you pass inspection with the check engine light on.

I will double check with a strong light if I can see some corrsion in the connections at the computer.

Thanks all for all the help

Jackate

I really don't think it will help, but the wiring diagram for my 2000 shows two black/tan wires from the PCM that are grounds. Supposedly grounded on the right side of the engine. It can't hurt to clean the grounds too.

Thank you, I will give it a try.

Sometimes it is better to remove both battery cables and touch them together for five seconds or so.

Thanks, I took your advice and removed both cables and touched them together.

I hope this works, Can't hurt..

Thanks again..

Jackate

Still no luck, the check engine light came back on, with the same code.

I can't figure this out, I guess it must be the computer.


At a loss with this one!

You checked for 5V going in. Have you checked for voltage out? Check at the sensor, then check the wire where it goes in to the ECM to see if it is the same. Did I miss where you gave your model year?