1999 Pontiac Grand Am GT Logo
Anonymous Posted on Sep 24, 2012

Coolant fans not working can overheats when driving slow

Ive been having problems with rad fans not kicking in ive replaced coolant temp sensors replaced fuses checked relays etc still no idea i recently took it to a gm dealership they tested the fan themselves and they would kick in on command when they hooked it up. The car is fine at highway speeds theres enough airflow going to the rad to keep things cool but as soon as i slow below 40km/h itll start over heating ive checked the fans connstantly to see but they wont kick on. i even recharged the ac on it but didnt last long i checked the fans didnt seem like they were on but the car was blowing cold air i drove it bout 5km to golf course and while the ac was on i was hearing a bit of a squeeling noise, parked get back to my car turn on ac no ac took it back to mechanics and a hose had blown so i didnt really get much of a chance to see if the if it kept the car cooler and i havent fixed ac since, the only thing i could possibly think of is wiring issues between temp sensor to fan or computer. and dont really wanna waste 400$ on labour at dealerships trying to diagnose any ideas thanks.

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Stan Ford

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  • Pontiac Master 3,131 Answers
  • Posted on Jun 16, 2015
Stan Ford
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The air con fan should come on with the air con switch. The coolant fan when operation temp is reached. check for battery voltage from the fan back to the censer and continue checking back till you find battery voltage, Could be a brake in the wiring or a faulty connection.

steve h woody

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  • Pontiac Master 2,551 Answers
  • Posted on Sep 24, 2012
steve h woody
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Did you get any obd codes ?? well there is a possible the power relay or ac relay is not working.

  • Anonymous Sep 24, 2012

    no havent gotten any codes or engine light the relays are in the fuse box right because ive swapped around like the cooling fan and ac relays and with ones i know work like hvack fan relay and still nothing

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5 Related Answers

Anonymous

  • 74 Answers
  • Posted on Aug 26, 2008

SOURCE: 2004 pontiac aztek cooling fans not working

relays control fans high and low. does fan come on with a/c on?hot wiring only will create more expensive problems in future!!!!! 2004 not 84

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Ronnie Wilson

  • 1596 Answers
  • Posted on Feb 04, 2009

SOURCE: 95 grand am radiator fan only runs with AC on

Cooling Fan Temp Sensor is the First thing You Check (with what you have described) Cooling Fan Should ALways come On When The A/C is turned On as A/C Adds A Load to Engine, If Temp Sensor is Faulty it Will Not Give GROUND Signal to ECM >For COOLING FAN >RELAY to Give ground and turn ON The Fan.
There ARE 2 temp Sensors that Serve Different Purposes 1 is for Dash READING GAGE & Or TEMP LIGHT the Other is For ECM or Fan Relay (SAME Thing) you Said>""can disconnect the sensor and fan continues to run" < This Leads me to think you Changed the Wrong One. Not Questioning your Skills Just Here to Help.
TEMP SENSOR FOR 3.1L V6 is Located upper RH rear of engine compartment, near exhaust system. Temp SENSOR for 2.3L Engine is Located in LH rear of engine compartment.
I Hope this Helps Lead you to a NON-OVERHEATING Pontiac.
Good Luck and Have A Great Evening. rejakwilson

Anonymous

  • 16 Answers
  • Posted on Jul 13, 2009

SOURCE: 1996 Grand Prix SE, cooling fans inop

try the fuse,if not that the wiring is bad from the fan to the switch.

Anonymous

  • 543 Answers
  • Posted on Oct 14, 2009

SOURCE: 3.1 L Grand Prix-cooling fan won't kick on, new

probably not a relay,check the coolant temp sensor to make sue its reading ok,if its misreading it will not tell the computer to turn the fan on

Testimonial: "Thanks, great help !!!!"

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Mike Broberg

  • 322 Answers
  • Posted on Jan 20, 2011

SOURCE: I noticed my engine light

Yes that is what the code means. GM usually uses two, one that makes the gauge work and one that tells the ECM what the engine temp. is. You need the one for the computer.

Testimonial: "Thanks for the info very helpful."

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