B 4 problem no cooling tell problem - Cars & Trucks

cooling of the engine? or you, A/c? cooling.
guess at engine cooling....
deep in side the PCM is answer
better, its now software , there. .

the pcm on new cars, have a EFI sensor called ECT
the designers woke up one day, and said hark, why have 3 sensors
1 for fan
2 for A/c
3 for EFI.
answer, was, you don't.
the FSM is free, to see, and look at that.
why not post the symptoms so we can tell you what is wrong and not guess.?

The ECT is the main engine coolant temp sensor
if this sensor is over about 215f, they PCM closes the rad coo

i must warn you , if you dont have A/c as some dont. the engine has
a fan clutch, as fully stated in the FSM.
http://www.jeep4x4center.com/knowledge-base/index.htm?utm_source=cj#service



free to look, posted 100s of times here. but there it is,
see engine cooling chapter.
then see the schematic for the wiring of the fan relay.
both pages tell you what you have.

if its HVAC cooling, then see HVAC

Hey chandralebea,

Try first by replacing the cooling fan engine temp sensor switch, as this may be the cause.



Good Luck

Under the hood with in the black fuse box. To locate the proper relay, the manual will tell you. a repair manual will tell you. your local dealer will tell you over the phone. or try a internet search engine.

cooling fans stay on, engine could be overheating, faulty cooling fan relay or pcm could be faulty.best get vechicle code scan before spending too much money you need scan to see what engine coolant temperature is,scanner can tell you if engine getting too hot could have partially closed thermostat,clogged radiator cores clogged engine block coolant passages clogged also the heater core, if engine not overheating the code scanner will tell you if you have faulty cooling fans relay or pcm failure.

Hi,
That cooling fan is for A/C condenser cooling. Not for radiator!
Tell us more!

FUSE AND RELAYS LOCATED UNDER THE HOOD IN THE ENGINE COMPARTMENT.TO LOCATE RELAY LOOK IN GLOVE BOX FOR OWNERS MANUAL IT WILL TELL YOU TELL WHERE THE COOLING FAN RELAY IS SINCE THERE ARE MANY OF THEM.

It has a cooling fan module,but other things come into this problem too,like the coolant sensor,witch tells the computer to tell the module to turn the fan on,and then off,also,check the cooling fan to see if it is good,and the fuse for the cooling fans,

The cooling fan switch is built into the ECM. The ECM tells the fan to turn on at about 220 degrees. If you have a bad coolant temp sensor you might have trouble there. Usualy I find the relay or fan motor to be the problem. In some cases the ECM or CTS is the problem. I hope this helps.
Thank You,
Roy

The Temperature Control Sensor. TCP . It regulates the cooling fan or fans . Some vehicles have 2. Also check fuses and relays first though.

some condensation is normal, but the cooling fan has three sensors. one on the water bottle telling the fluid lvl. one on the thermostat that tells the fan to come on and one on the block to shut it down when it is too hot. test the one on the thermostat.