Headlight Problem |
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Headlight Problem |
yeahmag |
Feb 14 2014, 08:31 PM
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#1
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Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
I have a very strange problem. My headlights work fine until I start the motor. Specifically, with the ignition all the way on, but the engine off, the headlights work as expected. With the engine running they will not come on at all. If the headlights are on and I start the motor they turn off, but stay in the upright position.
Ideas? |
euro911 |
Feb 15 2014, 12:06 AM
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#2
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Retired & living the dream. God help me if I wake up! Group: Members Posts: 8,851 Joined: 2-December 06 From: So.Cal. & No.AZ (USA) Member No.: 7,300 Region Association: Southern California |
Bad relay?
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jcd914 |
Feb 15 2014, 02:47 AM
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#3
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
Could be the X circuit (accessory) in the Ignition switch. X circuit shuts down while cranking.With a failing ignition switch the X circuit may not get powered back up when the starter is released.
Jim |
Thestigz06 |
Feb 15 2014, 05:39 AM
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#4
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Aspiring Jarhead Group: Members Posts: 238 Joined: 22-February 11 From: Temecula, CA Member No.: 12,749 Region Association: Southern California |
I had a similar problem with mine, I found that I had a crack in the starter switch. After starting the car, try turning the key slightly back but not enough to cut the motor.
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Kirmizi |
Feb 15 2014, 09:53 AM
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#5
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Senior Member Group: Members Posts: 836 Joined: 12-February 06 From: Wyoming, US Member No.: 5,568 Region Association: None |
(IMG:style_emoticons/default/agree.gif)
I'd start trouble-shooting at the ignition switch. All sorts of funkiness can occur when they go bad. |
yeahmag |
Feb 15 2014, 02:35 PM
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#6
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Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
If the problem was with the switch I think I'd see other systems failing. Is there a relay that turns off the sub systems when cranking? The only thing that's not functional after starting is the headlights.
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Kirmizi |
Feb 15 2014, 10:35 PM
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#7
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Senior Member Group: Members Posts: 836 Joined: 12-February 06 From: Wyoming, US Member No.: 5,568 Region Association: None |
When my ignition switch was failing, the problems were intermittent and varied.
Just to try and narrow this down, no other circuits are affected? Running lights, radio, etc... and does it happen consistently? |
yeahmag |
Feb 15 2014, 10:45 PM
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#8
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Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
The headlights seem to be the only circuit effected. Where is the relay that cuts the power to them when the starter is cranking? I'd like to replace that one for good measure.
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yeahmag |
Feb 15 2014, 10:50 PM
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#9
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Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
I should mention that the parking lights and dash lights DO work.
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jcd914 |
Feb 15 2014, 10:50 PM
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#10
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
If the problem was with the switch I think I'd see other systems failing. Is there a relay that turns off the sub systems when cranking? The only thing that's not functional after starting is the headlights. There is no relay to turn off the accessory load, it all goes thru the ignition switch. Pelican has the wiring diagrams in their site and you can trace out the accessory power from the switch to a couple different fuses. There should be something other than the head lights that are affected if the switch is failing but I would still check it first, since it is a common failure. The wiring to or from the fuses may not be connecting correctly. Since all the connectors at the fuse panel are standard spade connectors it is easy to put connectors on the wrong fuse connector. Use the diagram to find the accessory wire fro the ignition switch and hook a voltmeter or test light and start the car, does it keep it's power? I worked with a tech that constantly drilled me with "Test, don't guess" and "Work smarter, not harder", good advise (a bit annoying but good). Good luck. Jim |
yeahmag |
Feb 15 2014, 10:59 PM
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#11
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Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
Ignition Switch
I think further up in this thread it mentions that the heater blower is affected by this circuit. Gonna go check that... |
Spoke |
Feb 15 2014, 11:00 PM
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#12
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Jerry Group: Members Posts: 6,989 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
"Test, don't guess" (IMG:style_emoticons/default/agree.gif) Wow. Awesome advice. Measure the voltage across the headlight relay before and after you start the engine. If you don't have a voltmeter, buy one. Let us know what you measure. If you need help measuring, we can help you measure pertinent points. |
yeahmag |
Feb 15 2014, 11:22 PM
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#13
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Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
Yup. No go on the heater blower AND headlights AFTER going to the starter position. Guess it's time for a new switch.
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Porschef |
Feb 16 2014, 07:00 PM
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#14
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How you doin' Group: Members Posts: 2,165 Joined: 7-September 10 From: LawnGuyland Member No.: 12,152 Region Association: North East States |
If you need to replace the switch, it's an easy job, but most importantly, do yourself a favor and buy one through Porsche, they're still available and won't need replacement in 6 months like some of the cheap Chinese units.
Figger about 35 clams.... |
Mblizzard |
Feb 16 2014, 08:30 PM
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#15
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
If you need to replace the switch, it's an easy job, but most importantly, do yourself a favor and buy one through Porsche, they're still available and won't need replacement in 6 months like some of the cheap Chinese units. Figger about 35 clams.... That is good advice. I replaced 3 of the cheap ones before getting a good German switch. (IMG:style_emoticons/default/headbang.gif) |
yeahmag |
Feb 17 2014, 12:03 PM
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#16
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Advanced Member Group: Members Posts: 2,422 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
Best price on an OEM unit I've found is $92. The aftermarket is $8. I've ordered both, but that is one hell of a price differential.
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ClayPerrine |
Feb 17 2014, 01:11 PM
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#17
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Life's been good to me so far..... Group: Admin Posts: 15,503 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
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Mblizzard |
Feb 17 2014, 01:16 PM
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#18
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
Best price on an OEM unit I've found is $92. The aftermarket is $8. I've ordered both, but that is one hell of a price differential. But you will probably replace that cheap one 10 times before the OEM one fails. I replaced the cheap one 3 times. Lots of work and down time compared to the cost. |
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