I have a 2002 Grand Cherokee that over heats only in stop and go traffic.

Asked by May 29, 2017 at 07:19 PM about the 2002 Jeep Grand Cherokee

Question type: Maintenance & Repair

I have a 2002 Grand Cherokee that over heats only in stop and go traffic.
Did extensive testing on the fan relay and motor and it checks okay. When
engine is cold and I turn on the AC the fans comes on and continues to run
while AC is on so I know the fan works. With the AC off and the engine hits
over heating temp the fan is supposed to come on but won't. It continues to
over heat until I turn the engine off to prevent destruction.  Why would the
fan turn on and off with the AC button but it refuses to come on when it
over heats? Also, once it hits the over heat temp the fan won't come on
when the AC is turned on (only when it is running at normal temp). Has a
new thermostat and radiator.

2 Answers

1,820

There's two things that the fans turns on for. One is the A/C and the other is high engine temperature. These are run by two separate controls. Apparently the temperature sensor on the engine is not calling for the fan to come on when it's hot. And you are wise to not overheat the engine, especially the 4.7 liter engine having aluminum heads and a cast iron block makes them sensitive to temperature extremes. On a related note, the 4.7 liter engine was known to have plastic water pump impellers that deteriorate with age, making the coolant circulate poorly. I hope this helps.

1 people found this helpful.

Electronic fan relay is bad. Common on Grand Cherokees. It's in a really bad spot behind the front bumper cover.

Your Answer:

Jeep Grand Cherokee Experts

  • #1
    inuevafreak
    Reputation
    2,270
  • #2
    Tom Demyan
    Reputation
    2,140
  • #3
    thejeepdoctor
    Reputation
    2,120
View All

Related Models For Sale

Used Jeep Cherokee
564 Great Deals out of 73,417 listings starting at $5,995
Used Dodge Durango
354 Great Deals out of 25,665 listings starting at $1,500
Used Jeep Wrangler
200 Great Deals out of 14,724 listings starting at $3,000
Used Ford Explorer
857 Great Deals out of 71,377 listings starting at $495
Used Toyota 4Runner
272 Great Deals out of 32,851 listings starting at $1,900
Used Chevrolet Tahoe
655 Great Deals out of 37,366 listings starting at $1,850
Used Ford F-150
2,240 Great Deals out of 188,601 listings starting at $1,200
Used Chevrolet Silverado 1500
1,805 Great Deals out of 155,478 listings starting at $1,490
Used Ford Mustang
342 Great Deals out of 39,604 listings starting at $1,000
Used GMC Sierra 1500
644 Great Deals out of 56,634 listings starting at $888
Used Chevrolet Camaro
291 Great Deals out of 26,764 listings starting at $2,700

Used Cars For Sale

2018 Jeep Grand Cherokee For Sale
68 Great Deals out of 48,065 listings starting at $19,776
2017 Jeep Grand Cherokee For Sale
180 Great Deals out of 5,172 listings starting at $17,995
2016 Jeep Grand Cherokee For Sale
46 Great Deals out of 1,711 listings starting at $16,998
2015 Jeep Grand Cherokee For Sale
355 Great Deals out of 8,782 listings starting at $12,900
2014 Jeep Grand Cherokee For Sale
127 Great Deals out of 3,786 listings starting at $10,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.