Printer Friendly Forum Posts - viper 4115 remote start won’t

1998 gmc Yukon won't start but will crank. Once I put key in and turn to run position it will work. My key doesn't have a chip and will crank with any key that's cut.....help.....the security light will flash once it attempts to start without key

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PG

Without knowing how you've wired it or the Yukon's wiring, you've either miswired something or left out something such as a second ACC or IGN.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

I do have a second accessory wire for the vehicle, it's brown, but it's for the radio power and such........I don't have any avalible wires on the viper to terminate it....I did notice when the remote start try's and fail, the security light flashes.....

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PG

That's the one, I'm not familiar with the 4115 but is there a secondary loom with a low current NEG output orange marked ACC?
If so relay off it.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

OK, just checked, heavy duty harness, pink/white. Is it used for anything? If not connect it to that brown wire and program the unit for second ACC, default is second IGN.
Otherwise orange in satellite harness, to relay 85, 30 amp fused constant 12 volts + to 86 and 87.
To the brown from 30.
If you're using a 5 pin relay, don't use 87a and diode across 85 and 86, 1N4004, band side to 86.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Ok......I understand what you are saying and I can do that, but what does that have to do with the non start?....according to the vehicle schematics it has nothing associated with the starting. Just accessories.

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PG

No idea, read my first line first post.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Sorry I should explain. The base Viper R/S units aren't sold in the UK and a Yukon is rare as rocking horse s*&t
BUT This is a common fault when newcomers wire up GM vehicles and have this problem.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

What are you using to interface with the Passlock II system in your Yukon?

Chris the OP believes there isn't one.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

I can start the Yukon with any cut key....the key doesn't have a chip

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PG

The keys are not chipped in this truck. The ignition cylinder is resistance based. The anti theft is built into the cylinder not the key.

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If i Can't Install it I Don't need it Joe

Wow....thanks.what exactly do I need.

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PG

I like the idatalink stuff myself. Go to idatalink.com and put your car in. Where ever you order from make sure it's flashed for your truck. There is also fortin and dei xpresskit. I've had great success with I data products. Easy install,good guides.

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If i Can't Install it I Don't need it Joe

And still connect the brown wire.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

This site is the sh/t!!

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PG

Just one point, if the OP can use a plain key, where's the immobiliser, surely there would have to be a matching resistance in the key?

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

The resistance is in the tumbler. As the key turns in the ignition along with a connection made at certain points in the turning process for things like IGN1&2, ACC & Start, there is an additional connection that sends a resistance to the ECU allowing the vehicle to start.

i prefer to bypass the passlock altogether. keep gm vehicles from being stranded and make RS work a little more reliable.
olny if i am installing an alarm which usually have my own tricks added.
here is the GM passlock schematic for the 98 yukon.
posted_image

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yuk
quiet rural missouri, near KC.
If your system moves you physically and not emotionally, you have wasted your money.

Yukon has passlock 2 need to read resistance in yellow 20 gage wire from switch.

Find yellow and black 20 gage wire from ignition switch, use a multimeter to check resistance.To check, place emergency brake on, cut yellow wire,shifter on reverse, black wire from multimeter to black wire from switch (ground)red wire from multimeter to yellow (cut) toward switch try to start and hold (read resistance)try same way with other side yellow wire.use the higher resistance value. find a resistor. Connect one side of resistor to black wire from car, the other side to yellow going away from switch. tape the yellow wire going to switch.Hope this works.( do not forged to place car in park to try.)

Ok.....all the info from here was pretty good, I found all the wires to bypass the pass lock. On another forum a guy told me to get a 4.7k and connect it to the yellow20g wire and the ground, I did that. Then he told me to do a key learn...10min on then off, wait 5sec and start, which it did start. The following day I went to start it and it only just crank, no run. The security light was flashing, not to mention it stayed on the day before after I put the 4.7k in but it still ran with the light on. Can anyone tell me what's going on?

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PG

You need to read what the resistance is from your key cylinder (yellow wire). Learning a new value only works temporarily. Match to what the key cylinder is giving you within +/- 10% (closer the better) and it will work without fail. posted_image

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To master and control electricity is perfection. *evil laugh*

I just re-read your last post. Which side of the yellow wire did you put your resistor on? You did cut the wire correct?

The security light staying on tells us that you never reconnected it, or connected your bypass to the wrong side of the cut.

With the security light ON the vehicle is totally ignoring the passlock system.

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To master and control electricity is perfection. *evil laugh*

https://www.gmupfitter.com/publicat/bull/bull26.pdf

This is some good information on how passlock works. Ignore the toggle switch installation, or if you decide to follow it I think they describe the operation of a standard 12v toggle switch backwards. At least the old copy I have did.

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To master and control electricity is perfection. *evil laugh*

Ok...got it. I used the orange and black20g instead of the solid black, found the correct resistance 1.37k.....did the 30min learn...boom!! Light off engine running. No problem......you guys don't know how much y'all help me.

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PG