The PCM- engine computer , energizes the relay ! Is the PCM turning it on ? You could test it with a volt meter or a test light . Does it come on when you turn on the A/C ? If you pull the relay out of the place it plugs into an look on the bottom you should see 4 set's of numbers . 30 & 87 . one of these will have B+ voltage an the other goes to fan . If you jumped this two the fan would run . Now the other numbers 85 & 86 are the control side . One will have B+ voltage the other goes to the PCM . The PCM side one can be tested by hooking up test light to positive voltage an touching the point of test light to 85 or 86 ,which ever doesn't B+ voltage . start the vehicle ,turn on A/C if everything is all right on the control side the test light will lite . The PCM should turn on the fan when engine temp. reaches 212 degrees . You could test that with a up scale scan tool .
Pull the plug off the temperature sensor. This throws the PCM in default mode. The fans should come on at high mode. If not look to wiring, fuses, relays and the PCM. Scanner helps a lot.
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The PCM- engine computer , energizes the relay ! Is the PCM turning it on ? You could test it with a volt meter or a test light . Does it come on when you turn on the A/C ? If you pull the relay out of the place it plugs into an look on the bottom you should see 4 set's of numbers . 30 & 87 . one of these will have B+ voltage an the other goes to fan . If you jumped this two the fan would run . Now the other numbers 85 & 86 are the control side . One will have B+ voltage the other goes to the PCM . The PCM side one can be tested by hooking up test light to positive voltage an touching the point of test light to 85 or 86 ,which ever doesn't B+ voltage . start the vehicle ,turn on A/C if everything is all right on the control side the test light will lite . The PCM should turn on the fan when engine temp. reaches 212 degrees . You could test that with a up scale scan tool .
Pull the plug off the temperature sensor. This throws the PCM in default mode. The fans should come on at high mode. If not look to wiring, fuses, relays and the PCM. Scanner helps a lot.