pwb

Hi, my dashboard temperatur gauge dont work, the temperatur sensor has correct ohm and when grounding violet wire at the temperatur sensor the gauge should read max, but its still at low. Could it be some loose connector some place or does the wire goes from the sensor to the dashboard?

Grand Cherokee Laredo 1993 4.0L

/pwb

pwb

Some update that maybe help. When turning the ignition key on the temperatur gauge needle rises from bottom to the lowest number (40 celsius) so the gauge must be okey. Is there some of the contacts under the dashboard on the left (drivers) side that i can dissconect and measure on to see if the wire to the sensor is broken? Someone says that the wire dont go directly to the gauge but to a computer, is that correct?

SeriousOffroad

Replace the sending unit on the rear drivers side of the head.

pwb

But the sensor is okey i think, i measured the sensor and it has okey ohms, when cold (20 celsius) it was about 13kohm and when hot it go down to 900ohms (85-90 celsius?) But if i ground the violet wire then nothing happens with the gauge.

Bustedback

X2. It may check out ok with the ohm meter, but the sensor could be covered in muck inside the head, or any number of other things causing it not to work. It's cheap and easy to replace.

pwb

I will replace the sensor to test that, but another question, does the sensor goes to a computer or to the gauge?

cmow5

Mine is out too. If you saw my other post I had a Jump Start fiasco! My radio and temp gauge are broke. Where exactly is the sensor? Be as detailed as possible I am no Mr. GoodWrench, I bet Mrs.GoodWrench has got a few up on me as well! Thanks for your time.

jronald

If you ground the sensor wire, the gauge needs to read HOT. As you said, when you ground it, it does not. If you have a bad connection, it should read low so to answer your questions in no particular order.
Swapping the sending unit, probably wont make a difference.
Could be a bad connection causing it to read low.
Could be a bad gauge causing the issue

You should be able to read the resistance across the gauge and tell for sure.

Ron

pwb

http://www.justanswer.com/jeep/1h4rp...operating.html

pwb

But, goes the sensor directly to the gauge? someone said that it goes to the ECM since there is only one sensor in this engine?

tiwvr1

there are two sensors, guranteed, prob one on the thermostat houseing, and one on the head, not sure where though.

Bustedback

left side (driver side) toward the rear of the cylinder head is for the gauge, the one on the t-stat housing is for the PCM.

pwb

Is this for the PCM? http://www.justanswer.com/jeep/1h4rp...operating.html

pwb

I have taken two pictures where i think it is, but how is it possible to change that in a easy way Is it the correct sensor?

Bustedback

That one is for the gauge.