Black button under steering column on 1985 D30 CUCV truck--What is it?

Anyone know: What is the black rubber button under the steering column (slightly to the left) on the 1985 CUCV truck? Pushed it while driving the truck and it seemed to momentarily kill all the power in the cab...kept running and driving though, thankfully...

Don't hold it in. It is the auto ejection switch. When you reach Ludacris speed it is useful to escape the horrors of the 6.2 engine detonating.

I really don't know maybe someone put it in there as a manual glow plug switch. But it is not stock. The 2 toggle switches on the left side of the steering wheel are stock. Maybe the killing power was the glow plugs being activated. Good Luck. Post a picture and check out where the wires go.

Thanks, I get a picture. Glad the ejections eat was disarmed. I've seen other pictures of other CUCVs that have the black button AND the two toggles you mention...mine does not have those toggles...a manual glow plug button is an interesting idea though.

I second the glow plug guess, but thats all it is a guess! I did a bypass on a truck and that sounds like the HD switch that I used and about where I installed it.

Well that could explain both:

1. The hard starting when not using the button...(I only used the wait light which may not be actually tied to any actual type of heat sensor as I had assumed)...
and
2. The huge power draw when I pushed it because I know I was running on near dead batteries to begin with...

I'll attach a pic when I get back around the truck

Thanks again,
Jake

Krem, there's an easy way to do a manual GP switch that is very popular. It works well, and did I mention that it's easy? All you need is a momentary switch of some kind, and you ground one side (one of the terminals) and the other connects to a light blue wire that feeds into the GP Card controller. Trace the wires from your switch and see if they make those connections. If so, now you know what it is.

Thanks Marcus, I'm not near the truck right now but as I read your note and several others on SS I'm now 99% sure that that is a manual glow plug momentary switch...it's interesting to me that the wait light still works without me having used the switch at all yet. (I've had the truck a week and just got it running yesterday...without using that mystery switch...but it was a hard long cranking start through a jump of a HMMWV, I think I mistakenly assumed the "wait" light was actually telling me that the glow plugs were working correctly.) Now, I have the matter of dead batteries...what kind of batteries do you all recommend for CUCV? so I can test this switch properly next time?

They seem to work just fine with any quality battery. I'm trying to remember if I'm using Group 58 or Group 34 in mine.... They work fine with the standard trays and hold-downs. No need for the huge military batteries unless you need to sit monitoring the battalion freq all night.

Group 31 is about as good a fit as any. I shy away from 6TL in a CUCV. I don't think the extra mass and weight is worth the effort. But to each his own. Make sure the batteries are secured as they were from new. I would hate to see your batteries fall thru the thin rusty inner fender unsupported. Good Luck. And do away with the manual glow plug system. It really is not all that difficult to get it stock and reliable. They still sell the new and improved glow plug circuit cards. Be Safe.

Hey fellas - that black button energizes the Turbo Encabulator. Ask me how I know.

Sharecropper, thanks for the heads up. I don't think the 1985 had the quasistatistical regeneration parametric oscillator on the glow plugs yet so I doubt it could run the turbo encabulator without the card upgrade that cucvrus mentioned....which I will look into.

Kremlin said:

Sharecropper, thanks for the heads up. I don't think the 1985 had the quasistatistical regeneration parametric oscillator on the glow plugs yet so I doubt it could run the turbo encabulator without the card upgrade that cucvrus mentioned....which I will look into.

Click to expand...

Yep. He's going to fit right in here....