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P1660 code fans wont run tried everything installed jump wire with fuse link still run but still have code p1660 my scanner says its a high idlea lamp control circuit looked it up on internet said p1660 code was cooling fan control circuit

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Posted on Jan 02, 2017

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SOURCE: replaced both cooling fans all

when you first start the vehicle the fans whill cycle automatically. when the engine reaches temp the fans should kick on if they don't it is most like that you have either a weak relay or a loose wire very seldom would it be a severe ecm malfunction. please rate this solution

Posted on Aug 29, 2008

  • 607 Answers

SOURCE: cooling fan wont kick in

Could be the FAN MOTOR, COOLING FAN TURN ON SENSOR, even the PCM. There are 2 fuses . Also check fuse panel under hood in engine compartment

Posted on May 08, 2009

  • 607 Answers

SOURCE: 1992 Cadillac Coupe Deville blower fan runs all the time

The BLOWER MODULE is located on the A/C EVAPORATOR housing located UNDER THE HOOD passenger side firewall. Has 2 electrical connectors. Mounted with 4 screw bolts.Hope this helps

Posted on May 21, 2009

  • 6674 Answers

SOURCE: how do you fix a gm obd2 code p1660 output circuit

It's probably a bad connection to cooling fans, bad cooling fan, or relay in that circuit. Another spot to check is to clean backside of fuse block under hood, as they have been known to corrode up & cause similar problems.

Posted on Sep 17, 2009

  • 173 Answers

SOURCE: 1999 cadillac deville overheats

every thing that is electric needs a power and a ground if running a new wire to the fans i would prefer you to use a inline fuse this will keep the wire from catching on fire. u could run the power wire to a fuse that is ignition switch 1,2,3 one of these will work so when u turn the key they kick on. also the ground could be a bolt on the bottom of vehicle. use a test light and see if that wire hanging down is a power wire. hope this helps

Posted on Apr 09, 2010

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Why wont the headights or running lights work on my 2002 Buick LaSabre?

There are several reasons why your headlamps an running lights don't work , the headlamp switch is a good one ,plus relays an the DIM - dash integrated module an associated wiring ! Here is how the headlamps work , right out of Buick factory service info !
The dash integration module (DIM) provides battery positive voltage to the signal circuits of the headlamp switch. The signal circuits include the headlamp switch headlamps on signal, the flash to pass switch signal and the high beam input. With the headlamp switch in the ON position, a ground path is available for the headlamp switch headlamps on signal circuit of the DIM through the headlamp switch. The DIM provides ground to either the headlamps high beam relay control circuit or the headlamps low beam relay control circuit of the low beam circuit. The position of the headlamp dimmer switch determines which relay control circuit has ground. The DIM supplies battery positive voltage to the relay control circuits, if the headlamps are necessary. The fuse block - underhood supplies battery positive voltage to both relay switch circuits. When the low beam relay control circuit is energized, current flow is to both low beam fuses and to the low beam headlamps. The headlamps have ground at G103 and at G401. When the headlamp high beam relay control circuit is energized, current flow is to both high beam fuses and to the high beam headlamps. The high beam circuit is divided into a left and right side circuit. The current flow of the left high beam is from the fuse to the left high beam lamp. From the lamp, the current flows to the normally-closed contact of the DRL relay to G103. The current flow of the right high beam is from the fuse to the right high beam lamp. From the lamp, the current flow is to ground at G401. When the headlamp dimmer switch lever is pulled toward the driver, the flash-to-pass switch closes. This grounds the DIM flash to pass switch signal circuit. In response to this input, the DIM energizes the HDLP HI BM relay. Both high beams remain on until the driver releases the switch handle. If the low beam headlamps were on during a flash to pass operation, the low beams remain on. The headlights may be switched to high beam with the opposite movement of the headlamp dimmer switch lever.
By running lights , do you mean park lamps or day time running lamps ?
Park, Tail, License and Marker Lamps
The park lamps, including the license lamps, are turned on when the headlamp switch is placed in the PARK or ON position or anytime the headlights are requested. The fuse block - rear supplies battery positive voltage to the switch contacts of the Park LP relay. When the headlamp switch is in PARK or in ON, the park lamp switch on signal circuit of the DIM has a ground path. The DIM provides battery positive voltage to the control circuit of the Park LP relay. When the park lamps and/or the tail lamps are ON, the DIM energizes the park lamp relay control circuit. This closes the switch contacts. Current flows from the Park LP relay to the LH PARK LP and the RH PARK LP fuses. From the fuse, the current flows to the park lamps. The left park lamps are grounded at G103, G401 and G402. The right park lamps and the right tail lamps are grounded at G103 and G401. The DIMR fuse supplies battery positive voltage to the license lamps and to the DIM instrument panel lamp fuse supply voltage - 1 circuit, for interior lamps dimming. The license lamps are grounded at G401.
The best advice I can give is that you take this to a ASE certified professional repair facility unless your a qualified automotive electric repair person !
Diagnostic Starting Point - Lighting Systems
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1 Answer

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Check the small wires going to the starter solenoid. Hook up a voltmeter on the wires and see if you have power in the crank position. The ignition relay may be why power is not going through the keyswitch. The fusible link, probably not a problem if the engine runs.

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Cooling fan wont come on causing car to run hot

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Mar 08, 2011 | 1999 Chevrolet Cavalier

1 Answer

Blower motor not working at all,,the fuse is good and the fan blows if i jump it to the battery

HI Get a test lamp.With blower control switch on high ,remove power wire from blower motor,see if you have power at wire ,if not check for power at blower resister which is mounted next to fan motor.You should have power on two wires,one coming from switch the other going to fan.If you have power going to resister ,the resister is bad ,if no power to resister, switch has a problem Good Luck

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I have a 99 Jeep Grand Cherokee, that is running hot, cooling fan is not working has a ground doesn't have power. If I jump it out the fan works. What controls the power?

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