Remote Start

Hello, im new around here and was referred over here by someone. A while ago, i had drove my car, and shut my car off and the starter of the car just started turning over randomly and would not stop.. I yanked out the remote start brains and it stopped. Ive been attempting to fix it and learned when i put 12V to the module power pin, the starter just turns over.. Ive checked the transistors and diodes, and found one diode that is not reverse bias and i removed it from the board but then it showed theirs nothing wrong with it. I put a new diode in though and now that one shows it.. I can attach pictures of anything if needed.. Never had an issue till this.

Any help is appreciated.

Thank you,
TheKidInBuff

Pics of both sides of the board would help.

Welcome, TheKidInBuff!

Year and make of your car? Where was the remote when this happened?

Hello cowboybob lol

Its a 2002 Pontiac Grand Prix. I was just sitting in my car and turn the igntion off and it all of the sudden happened. While it was going on, i pulled the key out of the ignition and sat there very confused

Here are some pictures:








Id shrink the pictures but idk how.

Check the transistor near the big relay - Might the the cause of this

Okay i did and heres what i got for the transistor near the big relay:

When i connect the Negative to the base and positive to the emitter, i get 807 in the diode setting and about 3k resistance.

When i connect the Negative to the base and positive to the collector, i get 958 in the diode setting and about 9.5k resistance.

When i connect the Positive to the base and negative to the emitter, i get 722 in the diode setting and about 3k resistance.

When i connect the Positive to the base and negative to the collector, i get 595 in the diode setting and about 9k resistance.

When i connect the Positive to the emitter and negative to the collector, i get 714 in the diode setting and 12k resistance.

When i connect the Negative to the emitter and positive to the collector, i get 1500 in the diode setting and 12k resistance.


Thank you for reading/helping so far.

Is the board a factory install, or after market?

If the latter, can you give us the Brand name or some other additional identifier for the PCB? There are more than one remote starter rigs out there and they are not (as you would guess) the same.

I googled the apparent board model number and managed to bring google to it's knees (only 1 hit!!).

At a cursory glance, your various resistive tests are generally inconclusive, as is often the case when testing components in situ.

But, since the board is forcing a starter "ON" condition (relay energized), I wouldn't suspect the transistor driver circuit for the relay, but rather the driver circuit for the transistor itself (and/or components all the way back to the input signal to board).

Can you provide the wiring harness(s) pin outs? (No need for the starter connection, although there are two relays. Any idea what the second relays does?)

This one's going to be tough (for me, anyway) without a schematic.

I suggested this because I have had situations where the transistor brokedown and was permanently "ON". Remove the transistor from the board, and test it as if it was a "transistor switch circuit"

It is aftermarket. Its a Scytek G40RS model.

Here is the manual for it. If you scroll all the way to the last page, it shows what pins are what.
http://auto.manualsonline.com/manuals/mfg/scytek_electronics_inc/g40rs.html?idRes=16629448

If i do not plug in the power for the module, it doesnt do it.

Is that big black box a relay? Theres 3 if that one is. I thought it was. The two littler ones are for the parking lights. At least one of them is i know.

This is surely a pain but im having fun learning. lol

OK.

Yes, it would appear that all three black boxes are relays. The outermost little relay I believe is the starter relay.

For starters, I think it's best to point out a few issues.

1. This device is programmable. What that implies is the use of a fairly sophisticated digital microcontroller that would be extremely difficult to diagnose and, if need be, replace (uc not socketed).
2. Multiple inputs from multiple vehicle operation sources, any one of which may affect the device's operation.
3. Evidence of a fairly obvious device error (uncontrolled starter operation).
4. I was unable to find a schematic for this device, without which a diagnosis of the circuits is virtually impossible.

As a point of interest, I found a New replacement unit here:
**broken link removed**

As you can see, the price is only $49.95 USD for a complete, new replacement.

While I understand your desire to repair this device, my experience tells me to suggest a simple replacement.

Now, since the only command that should actrivate the starter relay is from one of the remotes, you might try removing their batteries and replacing them. It's a long shot but worth trying.

If, however, that does not clear the error (uncontrolled starter operation), I would just replace the hardware (controller and remotes).

As a side issue I once had a Range Rover and I hit it with a pressure washer underneath. It was on a ramp and it started to drive itself forward and off the end of the ramp. It dropped off about 8 feet with no damage thanks to a good chassis.
Cause -Water in the starter motor. --battery left hooked up and car in gear for safety...
Just in case it fits here.

This all sounds pretty terrifying... I'm sure there's too much electronics in cars these days!

The power transistor that drives the relay would be an obvious culprit, but I wouldn't expect it to be intermittent. If the fault's intermittent then it's more likely something complicated and, as has been suggested, really hard to diagnose.

The two smaller relays are in fact two separate relays coils within one package.
So there are five relays on the board depending what the biggin is.

https://www.mouser.com/catalog/specsheets/103.pdf

I've had this on an austin mini, tuned out to be the relay contacts welding togther, started sticking untill finally the starter wouldnt stop.
Are you sure the starter relay is ok?