Bypassing neutral safety switch?

[dean2526]

I am having problems starting the car (I only get the one click from relay/fuse panel). I have tried everything (all relays are seated, battery is fine, etc.). The only thing I can think is the neutral safety switch is somehow preventing the car from starting. I have jumped the cold start valve wire to the jumper post and the car starts, so I know the starter and battery are fine. I have tried moving the car and shifter from park to neutral and nothing changes. Can the NSS go bad to where it just prevents the car from starting altogether? Can I bypass it?

[Bitsyncmaster]

The neutral switch only affects starter operation. Are you saying your starter is not cranking? Or do you mean the starter cranks but the engine does not start?

[Helirich]

You really shouldn?t start a new thread about an ongoing problem. Your other thread gives us more info.

Anyways, as Bitsy pointed out, the neutral safety switch only interrupts the starter, so jumping the cold start valve would not help if the NSS was bad.

[dean2526]

The neutral switch only affects starter operation. Are you saying your starter is not cranking? Or do you mean the starter cranks but the engine does not start?

When I jump the car of the cold start valve wire, the starter works fine and the car starts. So there is nothing wrong with the starter in my eyes. And I've checked the relays they are fine. Im trying to eliminate everything.

[dean2526]

You really shouldn?t start a new thread about an ongoing problem. Your other thread gives us more info.

Anyways, as Bitsy pointed out, the neutral safety switch only interrupts the starter, so jumping the cold start valve would not help if the NSS was bad.

Understood, this was a new question of just how to bypass the NSS as that thread had ended with no resolution.

[Bitsyncmaster]

When I jump the car of the cold start valve wire, the starter works fine and the car starts. So there is nothing wrong with the starter in my eyes. And I've checked the relays they are fine. Im trying to eliminate everything.

So your problem is the starter is not cranking with the key to start?

[dean2526]

So your problem is the starter is not cranking with the key to start?

Yes. I get one click from the relay bank and that's it.

[Bitsyncmaster]

Yes. I get one click from the relay bank and that's it.

Is the click when you turn the key to on or when you turn it to start?

The AUX relay will click when the key is turned to on. Also your RPM relay may also click then.

What is your VIN number? There is a modification to the start inhibit relay for early VINs.

[dean2526]

Is the click when you turn the key to on or when you turn it to start?

The AUX relay will click when the key is turned to on. Also your RPM relay may also click then.

What is your VIN number? There is a modification to the start inhibit relay for early VINs.

I have an '83, VIN 16974. Is there a way to bypass the NSS?

[Bitsyncmaster]

I have an '83, VIN 16974. Is there a way to bypass the NSS?

I don't have an automatic. Looking a my schematic my guess would be the white/yellow wire from the auto connector would need to be grounded or go to 12 volts. Maybe someone with experience with the auto can verify my guess.

[mike123]

The white-yellow wire needs to be grounded to bypass the Neutral Safety Switch.

Here is a video in the DeLorean Technical Help group that shows the behavior of the car when the NSS isn't working properly: https://www.facebook.com/groups/290720127800158/?multi_permalinks=2170490793156406

The issue I had above was not the switch itself but rather a loose connection somewhere. I wiggled the white-yellow wire and it seemed to regain continuity and I haven't had an issue since (almost three years ago).

I did install a toggle switch between white-yellow and a ground wire, just as a backup. I would like to rely on the NSS whenever possible, so the toggle is Off, but if I run into this issue again I can just flip it to On temporarily to get me going without having to poke around looking for a bad connection or frayed wire or whatever.

[dean2526]

I don't have an automatic. Looking a my schematic my guess would be the white/yellow wire from the auto connector would need to be grounded or go to 12 volts. Maybe someone with experience with the auto can verify my guess.

Yes, that appears correct, thanks.

[dean2526]

The white-yellow wire needs to be grounded to bypass the Neutral Safety Switch.

Here is a video in the DeLorean Technical Help group that shows the behavior of the car when the NSS isn't working properly: https://www.facebook.com/groups/290720127800158/?multi_permalinks=2170490793156406

The issue I had above was not the switch itself but rather a loose connection somewhere. I wiggled the white-yellow wire and it seemed to regain continuity and I haven't had an issue since (almost three years ago).

I did install a toggle switch between white-yellow and a ground wire, just as a backup. I would like to rely on the NSS whenever possible, so the toggle is Off, but if I run into this issue again I can just flip it to On temporarily to get me going without having to poke around looking for a bad connection or frayed wire or whatever.

Dumb question, but I assume the switch is by the shifter, so I need to look for the yellow/white wire in there. And that wire goes through the tunnel to the relay behind passenger seat? Are there any wires in the steering column that go to the NSS? I dont see it on any on the diagrams, but just double checking.

[dean2526]

Dumb question, but I assume the switch is by the shifter, so I need to look for the yellow/white wire in there. And that wire goes through the tunnel to the relay behind passenger seat? Are there any wires in the steering column that go to the NSS? I dont see it on any on the diagrams, but just double checking.

Can you give me the full details of how and where you put that toggle switch and where you hooked up the ground.

[Michael]

If I recall, there is an update on some early cars where 12v is not always directed to the starter. I believe it involved putting in a jumper on the relay and it was fairly simple. Do a search for starter inhibit relay.

Do it no matter what your vin because after 40+ years, anything could have been messed with. My car is a 56xx and it had the same issue. The mod fixed it permanently.

[mike123]

As far as I know, the white-yellow wire goes from the L-shape connector in the engine bay, through the bulkhead, and to the Starter Relay in the relay compartment. I don't know what happens after the L-shape connector on the transmission side. But since the Starter Relay is in the relay compartment, it's easy to access from inside the car.

I chose a ground on the AC Illumination Panel relay socket because it happened to be easily accessible. Ignore the "BTTF Clare Box" piece, but it's just essentially a toggle switch between the white-yellow wire and a ground.

I might suggest connecting white-yellow to a ground with a spade jumper or alligator clips or something like that, just to quickly test if this is your problem. Michael's suggestion about the starter wiring is a good one as well, though I thought all 1983's already had this wiring update performed.

72206

[mike123]

My picture is tiny and useless for some reason, but I'll just reiterate that you can connect the white-yellow wire to any ground in your relay compartment in order to mimic the Neutral Safety Switch thinking the car is in Park or Neutral.

[dean2526]

My picture is tiny and useless for some reason, but I'll just reiterate that you can connect the white-yellow wire to any ground in your relay compartment in order to mimic the Neutral Safety Switch thinking the car is in Park or Neutral.

UGH!!! So I checked all the relays again the the damn starter modification wire was disconnected from the circuit breaker. I have no idea how that happened, but it starts now. Thanks for all the ideas everyone.