Cruise control issue

BrianX128

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1990 F350 zf5 rwd cclb.

My cruise always has worked. Recently my clutch had to be almost pressed through the floor board to start, feared my firewall had cracked but turned out the clutch safety switch sensor was loose so I bypassed it. Then a few days later my e brake cable snapped. I used a clamp for garage door cables and got it back together, but when released it has a rubber band to hold it up so the e brake light doesn't come on.

Now I have no cruise. Does the e brake sensor light being off with my rubber bands mean I shouldn't trouble shoot there or is the light not a good enough indication that it's out of the equation?

Fuse is good that's about all I checked so far since it quit. It's still connected to the throttle cable area as well. Probably coincidence and I have vacuum or electrical issue somewhere else.. joy
 

crash-harris

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Clutch safety switch is your problem. If bypassed, the cruise unit has no way to know where it's at. IIRC, the power runs through it.
 

Dieselcrawler

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Yep clutch switch. Only 2 wires get tied together. They make it start. The rest just leave apart.
 

Desertfireguy

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Had the same issue on mine when I bought it. If you wire a switch into the harness where you bypass the clutch safety, once you start the truck (with the switch closed) you can then open the switch and get your cruise back. To restart, just make sure the switch is closed, otherwise you'll be cranking without success. Also good as a theft deterrent!
 

cpdenton

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You could do this.

Go find a salvage yard with a truck of the same year you have, but with an automatic transmission. Any f-series with an auto will do. Now, go under the dash and find the wiring harness for the clutch safety switch. Plugged into this harness is a plastic "box" that bypasses the clutch pedal altogether for the auto trans. Plug it in and don't bump the key while you are in gear, or push the clutch without killing the cruise.
 

BrianX128

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Well maybe I explained this kinda wrong. The switch is still plugged in down there, I just ran a jumper to the two not green wires [I think they were pink with a stripe] and now when I use my push button my clutch doesn't have to be pressed in to start it. But they are still hooked into the connector.

Is what I did tricking the system to "always" think my clutch is pressed in? I thought the green wires down there determined stuff for the cruise and I only jumped the other two together.
 

Desertfireguy

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If you just have it jumped with a short piece of wire, you are tricking into thinking the clutch is always engaged. If you swap the section of jumper wire with a switch (on/off, two position) you can turn it off and get your cruise back.
 
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