Cps Sensor Down

[crys36]

Not much trouble taking it out 36" 3/8 extension , 10mm socket and used coming above crossmember--piece of cake..Putting 1 back in looks like the trouble. NOW the sensor has about a 12" line going into a connector but I can't figure out how it comes apart and don't want to snap any of the little plastic locks that might be there. Its cold out so plastic really isn't to flexible. The connection also is very tight-probably water tight by the looks-maybe not. A little help please.--Chris

[Saudade]

There is a plastic clip that locks the 2 connectors together. You do need ti pry it up a bit to unlock them. Too much and you'll snap it off. I don't recall if the lock is on the sensor side or harness side. If sensor, don't worry about it. If harness, try soaking a rag in hot water and wrap the connector with it to warm it up. If you have a blow dryer, try that too.

P.S. they do have a seal inside to keep water out so you may have to wiggle it quite a bit to get it apart.

[crys36]

Thanks and I'm DONE for now. Found some corrosion on 1 of the prongs of the sensor . I'll check out the other side tomorrow when I pick up the CPS. Wasn't there a thread someone posted on testing the condition of the CPS by using an OHM meter. If so could someone direct me to it so I can just see if this 1 is really failed. Has some good magnetic power to it still been pickin up all sorts of stuff around the house with it---Thanks again-Chris

[GregA]

Originally Posted by crys36

... Wasn't there a thread someone posted on testing the condition of the CPS by using an OHM meter.

I think I posted that link in another thread, but the sensor has to be in the car to be tested (while cranking).

Basically this sensor is a magnetic "switch" that switches between Ground and 5 Volts as the metal gears move below it.

Here is the link again:

http://www.autozone.com/servlet/UiBr...3d8015245f.jsp

Take Care,

[oljeeptek]

Originally Posted by GregA

I think I posted that link in another thread, but the sensor has to be in the car to be tested (while cranking).

Basically this sensor is a magnetic "switch" that switches between Ground and 5 Volts as the metal gears move below it.

Here is the link again:

http://www.autozone.com/servlet/UiBr...3d8015245f.jsp

Take Care,

The Chrysler style cps works as above. I don't see a year mentioned in your post so I'd add the original style Renix system CPS ohm readings won't tell you much except if open or shorted. I think spec was 200-300 ohms roughly, but the Gold Standard check is that it should put out 500-800 millivolts(.5-.8v) AC at normal cranking speed. I have seen many failed sensors pass a simple ohms check.

The car will exhibit stalling at warm idle, no start/hard start, as it drops off. The gap between the sensor is what determines the output.

[Saudade]

If the contacts in the connectot were corroded, they could be the source of your CPS trouble. If you haven't already done so, try cleaning it out with some contact cleaner and q-tips/pipe cleaners/anything that will fit.

Then test using the link GregA posted.

[oljeeptek]

Originally Posted by Saudade

If the contacts in the connectot were corroded, they could be the source of your CPS trouble. If you haven't already done so, try cleaning it out with some contact cleaner and q-tips/pipe cleaners/anything that will fit.

Then test using the link GregA posted.

I just took a look at the above link. It is in error of the model year coverage. CPS sensprs up until '91 or so are not Hall effect units. They are voltage inductive. They have 2 sensor wires.

Hall sensors must have 3; one is 5v or 12v, one is ground, the third is the switched (Signal).

Is there any way to pass that info to the site owner?

[Dale Aeppli]

Originally Posted by crys36

Thanks and I'm DONE for now. Found some corrosion on 1 of the prongs of the sensor . I'll check out the other side tomorrow when I pick up the CPS. Wasn't there a thread someone posted on testing the condition of the CPS by using an OHM meter. If so could someone direct me to it so I can just see if this 1 is really failed. Has some good magnetic power to it still been pickin up all sorts of stuff around the house with it---Thanks again-Chris

http://members.cox.net/wilsond/cps/ Here is a site that maybe of help. Dale Sensor is a hall effect sensor.

[Saudade]

Hmmm.... Never noticed that before. Checked on my '88 and looks like there's only 2 wires (I think I found the right connector). AutoZone shows different part numbers for an '88 vs. a '96.

From the '88 FSM:

ENGINE SPEED SENSOR (CPS) TEST

1) Disconnect the engine speed sensor connector from the ignition control module.

2) place an ohmmeter between terminals "A" and "B" (marked on the connector). On a hot engine, the resistance reading should bebetween 125-275 ohms.

3) Replace sensor if readings are not within specification.

[Dale Aeppli]

Originally Posted by Saudade

Hmmm.... Never noticed that before. Checked on my '88 and looks like there's only 2 wires (I think I found the right connector). AutoZone shows different part numbers for an '88 vs. a '96.

From the '88 FSM:

ENGINE SPEED SENSOR (CPS) TEST

1) Disconnect the engine speed sensor connector from the ignition control module.

2) place an ohmmeter between terminals "A" and "B" (marked on the connector). On a hot engine, the resistance reading should bebetween 125-275 ohms.

3) Replace sensor if readings are not within specification.

I think on his first post he stated it was a 2000 cherokee if so it is a Dis system. after 91-92 they went to a hall effect sensor. never changed one on 2000 but on my 97 it has three wires. 3 flat pins. Dale

[Saudade]

Crys36's profile says 2000.

However the AZ site link says it's for 84-98. I use the AZ site a lot for diagrams and test specs. Never used the CPS link because I figured out my bad one a different way.

[crys36]

Yup its a 2000 Jeep Cherokee Sport 4.0 ltre with a 3 wire Sensor. 1 Prong does have some green multch but Jeep Parts was Closed yesterday so I'll get it today. I know its bad was just wondering if I could test it on the table. Makea a great way to take your woman fork from her when she puts it down on the table though.Or taking her car keys. Thanks for all your help--Chris

[oljeeptek]

'2000 is definitely a hall sensor.

To test yours, plug it into the harness, turn the key on and stick a wrench against it. It should pull the voltage on the signal wire to zero, and return it when pulled away. It will also probably kick the asd relay on. Do it enough times you might be able to get the pcm to set a missing cam sensor code.