Question about 1998 GMC Jimmy

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1998 Jimmy SLT heater problem

The blend door keeps cycling from hot to cold no matter what setting it is on. Went to auto wreakers and tried a new control switch assembly no luck. please help

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  • Maltt Sep 24, 2008

    I had removed the electrical connection to the motor and checked for power and there is only power to one wire {brown] no matter what position the control is in.-- I will check the motor just to be sure.

    Thanks Maltt

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If the blend air door keeps cycling even if the setting is hot or cold this tells you that the thermostatic control sensor is bad. replace that and the problem will be solved.......please rate this.

Posted on Sep 24, 2008

  • lvllthms
    lvllthms Mar 06, 2012

    where is the thermostatic control sensor located .... and can you test it .. and if so what test is recomded

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With the key in the off position; remove the RDO BAT fuse for at least 10 seconds then replace the fuse; turn on or start the vehicle and try the A/C again. Removing the fuse should reset blend actuators.

Posted on Apr 24, 2009

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Look for the electric motor on the blend door remove it and see if the blend door is broken the fan will cause it to swing on its own

Posted on Sep 24, 2008

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