260z interlock TSB

[anthony_c]

laying a screwdriver across the starter solenoid contacts is an effective way of starting my car. but it is only slightly more graceful than hand cranking a model t.

i've heard rumor of a factory TSB that shows how to completely bypass the interlock. does anyone still have a copy they'd be willing to photocopy and share? or is this as simple as disonnecting a few harness connectors and inserting a jumper somewhere?

fwiw, my 260 has a build date of 7/74 and all of the relays are in the passenger foot well, not the engine bay. and no, none are labeled.

[240260280]

I'll get it out this week.

[heyitsrama]

Our friends over at HybridZ have some info, I removed the 2 connectors, but had to jump the reset switch to get power to the relay for the solenoid.

http://forums.hybridz.org/topic/80626-260z-seatbelt-interlock-defeat/

[anthony_c]

the car is pretty close to stock and the original harness is more or less intact, so i cringe at the idea of hacks that can't be reversed, but the idea of just laying in new wires, bypassing the whole mess, and relocating the interlock, relay, and emergency to my box of spares has its appeal.

this system is all problem, of no benefit, and i doubt anyone would ever complain about its absence.

Edited January 24, 2018 by anthony_c

[SteveJ]

Have you looked at the logic of the switches in the BE section of the FSM? 

These workarounds focus on getting around the Interlock Relay shown highlighted in red in the first attachment.

When the coil on this relay is energized, it keeps power away from the starter solenoid. Two solutions that I am sure that would work would require adding a jumper either at the Interlock Relay or at the Emergency Switch. The jumper would go between the Black/Yellow and Yellow/Black wires. 

 

There is one other solution that may work. If you disconnect the coil negative from ground on the Interlock Relay, that should defeat the seat belt interlock. From my reading of the wiring diagram it looks to be the Black/Red wire on the interlock unit. You want to disconnect this wire on the Interlock Unit side of the connector to prevent the chance of accidentally grounding the wire on the wire harness side.

 

[anthony_c]

@SteveJ, working up to that but squeezing this in btw other projects.

The problem is intermittent and when it does occur i can hear a relay in the footwell clicking, but nothing from the starter solenoid. Just thinking out loud, but i still haven't decided whether I want to

• purge the whole system and re-wire it like it was never there
• or add a parallel backup (maybe a momentary switch somewhere for when it decides not to work)
• or maybe just disconnect it, leave it in place and add a few jumpers as needed,
• or,
• or,
• or...

Edited January 25, 2018 by anthony_c

[SteveJ]

Any of the three solutions I provided should keep the Interlock Relay from interfering with starting. Good luck. Let us know what you do and how it worked.

[anthony_c]

i see your point about jumping at the relay or the emergency switch. either method gives the current a direct path and both are a quick, easy, and immediate fix.

do we have a personal preference?

[SteveJ]

Well, if you can find another emergency switch, you can cut the connector off if it and jumper the wires together like I described. That is probably about the easiest way.

 

[anthony_c]

On 1/23/2018 at 10:03 PM, 240260280 said:

I'll get it out this week.

240260280, i'd still be interested in seeing this if you do come across it. ill add it to my fsm as a reminder of what i did.

 

[anthony_c]

delayed update:  it was neither the interlock nor the relay.

it appears to be a loose connector (C5) under the dash and i'm sort of wishing it was the interlock instead.

[anthony_c]

but for future reference, a clearer view of how the interlock and relay fit in