mysterious plug under dash

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Oct 31, 2009 | 02:41 PM

Damonkr

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From: Cottage Grove, OR

mysterious plug under dash

I have been lurking here for a month or so now, having just bought an early 99 f250 psd, and have found a wealth of info. I have already fixed uvc harness, done ball joints, wheel bearings, installed slip joint grease zerk...while working on tq lockup mod I found some wiring andwhat looks like a diagnostics port. It isn't the obd II port so what is it??? There is a chip that is removable from it. When removed the truck won't crank. Also there is a red flashing light where the chip plugs in at.

Here are the pics

Thanks for any help identifying this.
kenny

Oct 31, 2009 | 02:50 PM

06silvercrew

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From: Albemarle, NC

Some type of an alarm or starting disabling system.

Oct 31, 2009 | 03:05 PM

Damonkr

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From: Cottage Grove, OR

Might note that the truck has factory keyless enty.

Just curious as to what this is since ill soon be installing a remote starter and alarm.

Oct 31, 2009 | 03:30 PM

ajohns

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My ex-brother in law worked at as a car detailer for awhile and used to install those. It's an ignition disabler. Pull the plug when you park and makes it harder to steal your truck. Just don't lose the plug.

Oct 31, 2009 | 05:23 PM

Damonkr

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From: Cottage Grove, OR

Thanks for the help!

After looking through the wiring under the dash I figured that must be all it is.

I think ill just leave it when installing the remote start.

Oct 31, 2009 | 06:32 PM

06silvercrew

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From: Albemarle, NC

I would ditch it. That way no chance of trouble later on and you not knowing whats what and were things are at. Just trace everything that is associated with it and remove.

Oct 31, 2009 | 06:51 PM

hanklin

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Joined: Oct 2003

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From: Here in No. Calif

I would leave it alone. If you keep it it will be a bonus to the alarm,as long as it is compatible. Trace the manufacture so you can extra chip. Any time you can disable your truck to keep it safe is a good idea

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Feb 21, 2010 | 04:06 PM

_Rick_

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Joined: Dec 2007

Posts: 784

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From: White Rock BC Canaduh

Kenny,

Photo #3 is a relay. Generally they are used for flood or spot lights. I can't tell/see if you have any, but I'll guess you either have some front lights or maybe even reverse addon lights?
If you don't have any additional lights,,, can you trace the wires?

If you take a close look at the diagram on the relay you should be able to figure out which wire runs to the addon accessory it sends power to and or (maybe) you can trace the wire that leads to a switch or system that controls the accessory (toggle or button switch).

Rick...

Quote:

Originally Posted by Damonkr