viper 791 1992 ford explorer not starting

What connections need to be made to get my friends 92 explorer to remote start?  I get the ignition to turn on, and the fuel pump energizes, then it all shuts off.  this is w/ door closed in park.  The module can flash lights, chirp, and lock/unlock, if that helps.  I checked the fuses.

Neutral safety, grounded (car has its own interrupt circuit)

I am pretty sure I did the ignition harness right. 

thanks

Program the tach...or program the brain for voltage sense if not using the tach input. The dei unit is default for tach and it won't work until you do either step listed.

Good Luck

So it will just shut down like i had described?  or how does it act w/o the tach hooked up not on voltage sense?  I would check the car but its like 30 minutes away right now.

thanks for the quick reply

Correct. As you describe the problem I can really see no other reason. If it was any of the shutdowns you would get no response to RS at all. That vehicle does not use any kind of factory immobilizer so thats out. The only other options are the start wire is hooked up wrong or poorly connected (I would think it safe to assume you double checked all that with a meter) or a bad unit...which is highly doubtful with DEI..they just are one of those brands that work out of the box 99.9% of the time if installed/programmed correctly.

Basically the system is showing response by powering up ignition and flashing the lights, but it won't crank it. As stated the unit comes out of the box default for tach...so..if you didn't program the tach (simply start the truck with the key...press and hold the valet until the led lights up.let off valet..turn key off...try remote start)...or ,program the unit for tachless if you didn't hook up the tach wire you would need to do one of those regardless before any further troubleshooting...but my money is on what I stated and it should crank once this is done.

The unit does not crank the starter unless one of those procedures is done...just the way DEI designs them..a failsafe way to make sure the installer has followed procedure.

Let us know if it starts after doing one of those procedures.

Did you program the tach sense??  IF not..read the directions and do so..if it still doesn't work..get back and we can figure it out.

If your explorer came from the factory with keyless entry then correct ..the doorlocks are positive. The dei module can power it..the outputs are negative and positive and requires no programming.

If it is a non keyless optioned truck you will need to do a "5 wire" relay circuit for the locks to work.

If you are not sure if keyless is in your truck because you have no remote with it you can check behind the left rear panel for the keyless module..if you have a factory remote then its definatly a keyless version.

Ohhhhhhhhh, im a terrible reader... have to program tach sense first.  got it, then given that i didnt screw anything else up... should be peachy right?

On the viper i noticed one wire is  +(unlock) - (lock)  and vice versa for the other... no need to diode isolate the neg signals?

thanks for your answers and patience

If i have problems, you should know by sunday afternoon.  hopefully earlier.

Yes..it "should" work fine once you program the tach..but if it doesn't..you needed to take that step first regardless since that unit does not remote start until it is programmed.

The DEI doorlock outputs switch neg. and pos.  This is so you can use them with neg or pos doorlock equipped vehicles///no diodes are needed since these type of vehicles use factory relays..so lets say for example the vehicle has pos controlled doorlock..that means the other side of the relay coil is neg. so when the doorlock output sends a positive to the lock relay..the doors lock. when you press unlock the same happens for unlocking..but at the same time the lock wire will then be sending a neg. to the lock relay..but it has no effect since the other side of the relay coil in this case is already negative. Vice-versa during lock. The worst you can screw up is switch the wires (a 50/50 shot)..then the locks work backwards when you press the remote...but no biggie...just switch the wires back again and they work fine.

Now..if the vehicle has no factory relays..the locks work by the factory switchs themselves reversing the polarity to the actuators..a heavy duty switch with thicker wires is a tale tell..not to mention there will be 5 wires at the switch instead of 3.

also note on your particular vehicle if it came with factory keyless entry (you will have a factory remote)it has factory relays and you can use the outputs directly..it is positve "3 wire"..typically on fords is a pink / YELLOW  and pink/green.

In that case you must use 2 relays and configure them for a "5 wire"..or aka "reversing polarity" configuration.