Question about 2008 Chevrolet Impala LT

2 Answers

Need wiring diagram of rear-window defogger circuit for 2008 Chevy Impala LT

Defogger not working. Light on button works. Fuse Tested Good. Relay clicks when button is pressed. No voltage on right or left contacts for rear window defogger grid. Have continuity across contact though. Now I need to know where to go back between the grid and relay to look for problem.

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  • Thomas Englert
    Thomas Englert Jan 05, 2014

    I had the same problem with my 2007 Imp and found the same connector with a burnt wire. Thanks treepeOple

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I just fixed my car to the exact question above, it took 20 minutes total. yes I\'m good with a wrench, but this fix doesn\'t reqire you to be.

Problem: Rear defroster doesn\'t work, but the fuse is good and the little light comes on on the button.

Answer: Go to front passenger kick panel where the "other" fise box is and remove the pastic panel, it just pops straight up. Under the fuse block is a white plug that connects front wire harness to the rear harness. this is where the problem is. pull the connector off the body, my plugslide straight back. Now flip the whole connector over, there you\'ll see the burnt spot on the plug. losse, corroded connection causes melt down. this stuff happens. my car has a purple wire going into the plug and a black one coming out, this is the rear defroster wire. cut the purple wire aleast a half inch before the plug and cut the black one coming out of the plug the same, always leave a little wire incase you ever want to reuse that terminal, standard rule. now take two butt connectoers and a four inch piece of ten gauge and splice the purple and black wires back together. lots of current so DO NOT use 12-14 gauage wire, it will melt. and Wa-La, its fixed!! since you dont have to do the trouble shooting and chase down the wires like i did, should take you ten minutes to fix.

Now if this doesn\'t fix your car, then don\'t pay me!!

If this DOES fix your car, then take your wife out to dinner with the $150.00 i just saved you from having to take it to the dealer,

(they would sale you new connectors and harness)

Posted on Jul 06, 2013

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  • Chevrolet Master
  • 36,376 Answers

Check for a broken or missing ground connection at the X2 terminal of the defogger grid. Then go back up the line from the grid to find where you are losing voltage. The black wire from the grid is spliced to a PPL wire and the PPL wire goes to the F1 terminal of the 40A BATT 3 fuse which you say checks good

Posted on Oct 30, 2012

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6 Suggested Answers

6ya6ya
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Posted on Jan 02, 2017

  • 120 Answers

SOURCE: 1997 honda accord - rear window defogger not working

check the grid ground

Posted on Dec 15, 2008

Tech jk
  • 102 Answers

SOURCE: 2002 Alero defogger

A common thing to fial on these- assumning the grid is ok, and wires are still attched to grid, is the rear def / antenna module. It is behind rt. rear quarter trim panel. The modules burn up, and also melt the connector. the module and connector would need to be replaced.

Posted on Jan 04, 2009

motor1258
  • 6674 Answers

SOURCE: rear defogger not working

Easiest way to test it is with a test light, $5-$10 at auto parts store or hardware store. Attach ground clamp to good ground source then lightly/carefully, touch grid close to where connection to it is with point of test light. If it lights, you've got power there, and you need to look for breaks in lines. Might save a lot of looking for something that is o.k.

Posted on Mar 22, 2009

alicantecoli
  • 22246 Answers

SOURCE: rear defogger grid is

has a wire come the rear screen heater ??

Posted on Jan 03, 2011

emissionwiz
  • 76846 Answers

SOURCE: I have an 08 Impala LT with rear defogger not

Did you check the defogger grid connectors to ground on the chassis, check both sides. So to do this disconnect the grid connectors and turn on the rear defogger, at one of the connectors to the grid you should have battery voltage. I am not sure which side the power comes in on so thart is why I said both, you must find a clean sheet metal chassis ground to connect the 12 volt test light ($4 at any parts store like Autozone) clip lead end to, use an ohm meter if you are not sure you have a good ground. Also make sure the engine is running when you do this test. Let me know what you find.

Posted on Sep 14, 2011

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