Cruise Control

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GTP51

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Taking It back to the beginning, we took off the TBi /manifold /heads/cam etc did a bunch of engine mods and fitted a Holley Sniper,results are fantastic very happy, mechanically the truck is set. We removed nearly all the engine bay loom and the complete ECU and every wire that plugged into it from the engine bay and either reconnected them to components as applicable or removed them. Every thing works except for the cruise control which did work before the engine upgrades. Under the dash there is this plug which plugs into the ECU harness and as far as I can tell is the cruise control harness.
Is anyone able tell me what interaction these wires have in the ECU and if there are any other Engine Bay wires that interact with the cruise control, save for the one harness that actually connects to the cruise control unit that mounts on the engine.
If any of you have fitted a Sniper and have a working cruise control please chime in.:cheers:

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Matt69olds

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Did you unplug the vehicle speed sensor? The cruise plugs into the speed sensor, it still needs the speed signal. Did you disconnect the vacuum hose at the brake switch? Is the cruise still plugged into the brake light switch?
 

GTP51

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Hi Matt, as I mentioned everything under dash is connected except for the plug as per photos
 

Matt69olds

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Is that plug part of the cruise harness? If so, I bet that plug is for the cruise control module. I think it clipped to a bracket about the gas pedal.

If that’s not it, I’m out of ideas.
 

GTP51

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Matt you get credit for trying lol, that harness does a few things, I’m hopeful some tech head can help out with this one
 

GTP51

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no one around it would seem
 

My78truck

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I changed out my cruise control. It is the Cruisemaster no resume system with just the button on the end of the turn signal. When I did replace it, there was a small white connector with 2 wires and the connection was up in the steering colomn. If that is your cruise control, you must have one of the later ones that has the resume function. Have you tried looking at wiring diagram? Might be helpful. I bought one off line that was laminated and was in color. Made it easier for me to trace the wires. Also, have you tried an internet search for information about your cruise control? I found the service training manual for mine online and printed it off. It has 4 different types of cruise control in it and I didn't see anything that listed the wire combo you are showing.

Sorry, didn't answer your question, but just some thourghs/ideas. :confused:
 

GTP51

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R10 Silverado half ton Stepside
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I changed out my cruise control. It is the Cruisemaster no resume system with just the button on the end of the turn signal. When I did replace it, there was a small white connector with 2 wires and the connection was up in the steering colomn. If that is your cruise control, you must have one of the later ones that has the resume function. Have you tried looking at wiring diagram? Might be helpful. I bought one off line that was laminated and was in color. Made it easier for me to trace the wires. Also, have you tried an internet search for information about your cruise control? I found the service training manual for mine online and printed it off. It has 4 different types of cruise control in it and I didn't see anything that listed the wire combo you are showing.

Sorry, didn't answer your question, but just some thourghs/ideas. :confused:
Thanks for the info and suggestions.
I have some 200 pages of wiring diagrams for the various iterations of these trucks and the one that deals with cruise controls, it would have been a huge help if they were in colour. What I’m trying to find out is , after further analysis, how does the ECM interact with the brown wire that goes to it from the plug I posted? Is it a signal wire? Is it a power wire. Problem is I can’t just fire up my ECM as the loom is chopped up and neither it or the ECM are in the truck. I will keep digging .
Cheers
 

My78truck

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Thanks for the info and suggestions.
I have some 200 pages of wiring diagrams for the various iterations of these trucks and the one that deals with cruise controls, it would have been a huge help if they were in colour. What I’m trying to find out is , after further analysis, how does the ECM interact with the brown wire that goes to it from the plug I posted? Is it a signal wire? Is it a power wire. Problem is I can’t just fire up my ECM as the loom is chopped up and neither it or the ECM are in the truck. I will keep digging .
Cheers
Sent you message with a link.
 

ak4life

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Brilliant thank you.:cheers:
Geoff
Could i get that link, having same issues...
Chris. You could text it to me 928 352 3191 or email [email protected] thank you
Also put cruise control in subject so ill know its not spam. Thanks again
 

GTP51

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Some info there that I didn’t know was available, now to clean the reading glasses let the fun begin
 

Dave Arends

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I would like to know what that plug is for too. Will be putting cruise back in after LS swap
 

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