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Interior Light Delay Relay help

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Old 04-28-2010, 01:56 AM
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AO
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Default Interior Light Delay Relay help

I think I finally found my battery drain culprit. I found that the interior lights do not go off after I close the door (ignition off). Plungers seem okay, so I guess it's the relay. Relay says 25s +- 5s, so I assume they should turn off within 30 seconds. After 2 minutes of holding the door plunger down, lights are still on. If I turn on the ignition, they go off.

So, I've pulled the relay to see if this saves my battery. I would replace it, but this relay appears to be $165+! Holy crap!

Is there a way I can test this relay or better yet, can I just jumper it so the lights come on when I open the door and they turn off when I close it (without the delay)?

Here's what the relay says... I have no clue how to read this. Any help is appreciated. Thanks.

Old 04-28-2010, 02:21 AM
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Alan
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The hatch pin switch makes them come on also even without the relay - check that.

Alan
Old 04-28-2010, 09:37 AM
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Except, if I turn the ignition on, the lights go out. If I then turn off the ignition, the lights stay off until I open a door. Once I open the door, the lights come on, and if I close the door (or hold the pin-switch down) the lights never go off. That is, until I turn the ignition on. This would indicate to me that there is a problem with relay.

Which pins would I jumper to make it an on/off operation and not a delay? Anyone know of an alternative relay?
Old 04-28-2010, 09:41 AM
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Ninespub
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Damn, Dem is some big hands!
Old 04-28-2010, 09:44 AM
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You know what they say...

Big hands, big hands!
Old 04-28-2010, 11:04 AM
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Alan
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Well you can try jumping TK to 31L - this will switch the lights directly with the pin switches.

Its a lot of load and they aren't likely to be reliable in the long term.

Alan
Old 04-28-2010, 11:08 AM
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Andrew - post a picture of the bottom pinout.

If you can find a compatible Pinout an alternative should work and give you some of the same features...

Pin - Function
==========
31 - Ground (needed)
31L - To interior lights (needed)
T/TK - Negative trigger from door pin switches (needed)
30a - Power for higher relay functions (optional)
15a - Ignition - truncates delay with ignition on (optional)
31Z - Negative Lock - truncates delay when locking (optional)

Alan

Last edited by Alan; 04-28-2010 at 01:16 PM.
Old 04-28-2010, 12:07 PM
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Will post tonight. Thanks Alan.
Old 04-28-2010, 12:49 PM
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I would install a jumper at relay socket where pin 15a goes, then use a volt meter to measure for it properly getting +12V (ignition) power with ignition key. Not likely, but your relay may be ok.

You could also take the cover off the relay and carefully resolder the electronics components.
Old 04-28-2010, 05:41 PM
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Here's the img. I did take the cover off and after a perfunctory review, I did not see anything amiss. I may try re-flowing the solder points.

Old 04-28-2010, 07:55 PM
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borland
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Andrew,

Don't forget that there is a third door contact for the rear hatch. That might be making the problem more confusing. If the side doors are closed but the rear hatch is not, the lights won't go out.

I mis-read your first post. It apears the relay is getting a proper +12 volt (ignition) signal.

If you post a photo of the insides, we can prescribe a bench test and repair.
Old 04-28-2010, 08:07 PM
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But, you can also do a bench test without taking the cover off. You would need your meter, some test wires, and a 12 volt battery.

Test the delay by applying battery positive terminal power (30a) and battery negative terminal ground (31). Then momentarily, touch pin TK with a wire to battery negative terminal. You should hear the relay activate. Then wait for the relay to time out and click again.

There's more you can test, but that's a good start.
Old 04-29-2010, 12:09 PM
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Originally Posted by borland
If you post a photo of the insides, we can prescribe a bench test and repair.
Here you go...







Old 04-29-2010, 12:10 PM
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Originally Posted by borland
But, you can also do a bench test without taking the cover off. You would need your meter, some test wires, and a 12 volt battery.

Test the delay by applying battery positive terminal power (30a) and battery negative terminal ground (31). Then momentarily, touch pin TK with a wire to battery negative terminal. You should hear the relay activate. Then wait for the relay to time out and click again.

There's more you can test, but that's a good start.
Plan to run that test tonight. Thanks for the advice.
Old 04-29-2010, 12:49 PM
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Alan
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Andrew based on the pinout of the Porsche relay - I don't think you'll find an easy alternative plug in.

Reason is the corner (small pin) location of the T/TK pin - common relays with less features would only use the 5 large terminal positions.

Alan


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