h151f clutch assembly Neutral Safety Switch

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danakittilsen

danakittilsen

10 Year
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Grande Prairie, AB
We (@gnarlynick2072 and @teedigs) are getting pretty excited to swap the 5spd into our 80s. There is one thing about swapping an h151f that we haven't seen adequatly addressed: The Neutral Safety Switch. Which would normally be found on the clutch pedal assembly, requiring the clutch to be depressed to ensure the vehicle is not in gear to start.
These transmission can be installed but with a small work around that will interfere with the cruise control, which can be fixed with another work around: a switch which disconnects that neutral circuit to allow the CC to function.

Apparently on early models there is no NSS, or rather the truck can be started IN GEAR. It seems possible that some of these models did not come with cruise control.
But later models must have had a factory h151f and factory cruise control without any conflict or need of some Frankenstein switch solution.
I've been looking on various parts supplier websites, toyodiy, and the FSM but I can't find any indication that there is a switch on the clutch assembly.
Apart from a vague reference by landcrusher80 (who in the end used a switch on his dash).

Does anyone know anything more about this issue?
 
OGBeno said:
Looks like you might need: 89531-60010: Transmission switch on the H151

How it is wired and operated you would probably need to get an EWD for an HDJ81 from the Japanese market.
Click to expand...

How would that work?..

I'm picturing a button switch which gets physically depressed when the clutch is pressed, like in the 4runners. However, not sure how this was done in 80s or 100s...

Otherwise there must be some ignition logic work around, or even CC work around. On 4runners in order to enable the e-locker to operate outside the parameters of the ECU (for example being able to engage over 5 km/hr) you physically cut the wires and the ECU doesn't include it in the logic. Perhaps something can be done to either of these items.
 
If you delimit the EPC to the manual transmission, you cannot get auto transmission parts--they will show "not applicable." Hence the NSS comes up as "not applicable" for M/T transmissions.

You will also notice that on the A/T transmissions there is an actual transmission control ECU and the M/T's don't have these.

Again, it is going to be worth your while to get a copy of the EWD for an HDJ81 and see how the NSS circuit is wired and what parts are associated--if any.
 
I put my search parameters for a '96 manual transmissiom.
This seems the most relevant

84540 SWITCH ASSY, NEUTRAL START
Not applicable

But of course it says not applicable.
I have the EWD at home. I'll start tracing colored lines when I get another case of beer and get home.
 
rather than have a switch that get's " pressed " along with the clutch pedal, you could use something like the brake light switch .. it is " pressed " all time

BTW our manual 80 don't have any NSS at all ..
 
This is almost a 10 year old thread - Anyway, working on getting the ducks in a row for the H152 swap into a 1998 HDJ80 with cruise control.
I found the clutch switch in the cruise control diagrams. 88280-14030 is the clutch switch and is installed into the pedal. This part does not show up for an automatic configuration.
Since the 1HDT does not have an ECU I assume the wiring is only for the cruise control. This means it will start in gear unless there is another circuit for that.

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mudgudgeon said:
Correct.
For Cruise control only
Not required to start.

My 1hd-t had no cruiser control. No clutch switch.
Click to expand...
So that means manual 80s would start in gear from factory? I assume this from driving older cars that also did not have a safety switch for starting.
 
Correct.

I would not want to have to depress clutch to start a manual 4wd that is used offroad.

There's times offroad with a manual transmission where its helpful to be able to stall out the engine, and do a key start, clutch engaged, in gear to restart.

Eg, can't complete a steep climb. Stall out the engine, resist the urge to put the clutch in.
Apply brakes
Disengage the clutch
Select reverse.
Release the clutch
Release brakes gently, and simultaneously restart with the key when you're ready to start your reverse descent.

Have done similar going down hill.
In Lo, 1st gear. On the brakes. Stall the engine. Do not depress the clutch.
You can use engine compression to continue to descend, in gear, engine off. Leave the clutch engaged, and key start when you're ready to proceed under power. This let's you descend slower than you can with engine idling. And more controlled than relying on brakes.

Both scenarios give you a very controlled, slow motion restart.
You are using engine compression for strong braking to secure the vehicle on a slope while you assess your options, shift to reverse or visa versa.
 
mudgudgeon said:
Correct.

I would not want to have to depress clutch to start a manual 4wd that is used offroad.

There's times offroad with a manual transmission where its helpful to be able to stall out the engine, and do a key start, clutch engaged, in gear to restart.

Eg, can't complete a steep climb. Stall out the engine, resist the urge to put the clutch in.
Apply brakes
Disengage the clutch
Select reverse.
Release the clutch
Release brakes gently, and simultaneously restart with the key when you're ready to start your reverse descent.

Have done similar going down hill.
In Lo, 1st gear. On the brakes. Stall the engine. Do not depress the clutch.
You can use engine compression to continue to descend, in gear, engine off. Leave the clutch engaged, and key start when you're ready to proceed under power. This let's you descend slower than you can with engine idling. And more controlled than relying on brakes.

Both scenarios give you a very controlled, slow motion restart.
You are using engine compression for strong braking to secure the vehicle on a slope while you assess your options, shift to reverse or visa versa.
Click to expand...
X2, I used to drive a VW Amarok with this setup and incredibly annoying to have to hold the clutch in whenever you tried to start.
Never met a manual cruiser that had a clutch switch to start, new VDJ79 will start in gear.

The only thing the factory clutch switch does is cruise control cancel.
 
The 80 I'm working on I put a nv4500 manual transmission in it I also didn't install a neutral safety switch I could have but didn't seem necessary.
 
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