1987 k5 Silverado. I am assuming the large box is for CC as there is a vacuum line switch there. I dont believe I have a drac on my year. Any clues?
CK5
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any body know what these are?
- Thread starter metalneverdies
- Start date
gray box I think is buzzer box .
blueish green is speedo vss unit for cruise .
blueish green is speedo vss unit for cruise .
There is a very small buzzer wired into the fuse box. It sits on the side of it. I dont think anything in the two pictures are part of a buzzer.
Sweet, I will definitely leave the vss and cruise alone. Just was curious what it all was / went to.
Sweet, I will definitely leave the vss and cruise alone. Just was curious what it all was / went to.
Yep, large vertical black "box" is the cruise module.
The whole panel to the left of it (with the flasher) is part of the "convenience" center. Some of it is tied into the key off/headlight on buzzer system IIRC. Not sure what the buzzer would be on the fuse panel, pretty sure I don't have one...might be a later deal, even though my panel is pretty much the same as what was used until 1991. Huh.
The VSS also feeds your ECM, FYI.
The whole panel to the left of it (with the flasher) is part of the "convenience" center. Some of it is tied into the key off/headlight on buzzer system IIRC. Not sure what the buzzer would be on the fuse panel, pretty sure I don't have one...might be a later deal, even though my panel is pretty much the same as what was used until 1991. Huh.
The VSS also feeds your ECM, FYI.
Hmmm. I have two flashers. One on the fuse block and the one next to the convenience center deal. I was wondering if that acts as a self resetting circuit breaker?
I dont have to worry about the ECM as I am going 5.3 swap. I was more curious for their functions so I can figure out how to wire up a cruise control from a 90's truck to my factory 87 setup.
90's as in still TBI, or Vortec?
Cruise stayed the same for a long time...even when (at least initially) GM changed over to the electronic cruise motor (instead of vacuum) the VSS input to the cruise was the same (2000PPM)...meaning at least the early electronic cruise motors will work with the '87. With the 5.3L, not sure...but I would start looking at early LS stuff (pre-drive by wire I suppose?) and see what they used as a cruise drive motor.
Whatever the LS uses for VSS is likely what the cruise uses too, so I would think it would be pretty easy.
One flasher is for turn signals, one for hazards.
Cruise stayed the same for a long time...even when (at least initially) GM changed over to the electronic cruise motor (instead of vacuum) the VSS input to the cruise was the same (2000PPM)...meaning at least the early electronic cruise motors will work with the '87. With the 5.3L, not sure...but I would start looking at early LS stuff (pre-drive by wire I suppose?) and see what they used as a cruise drive motor.
Whatever the LS uses for VSS is likely what the cruise uses too, so I would think it would be pretty easy.
One flasher is for turn signals, one for hazards.
Ah, maybe thats why my hazards dont work. I will have to swap the flashers.
I am keeping my 700r4 and the vss that runs in my np208 and am hoping to adapt that to the 90's CC. I have the vacuum setup from the 87 but would rather run the electronic setup. I have a vss adaptor to control the LS PCM.
The electronic one from the 90's was TBI. I cant remeber what year truck I got it from but is the 89-97 ish body style. The vortecs then were still tbi wither way.
I am keeping my 700r4 and the vss that runs in my np208 and am hoping to adapt that to the 90's CC. I have the vacuum setup from the 87 but would rather run the electronic setup. I have a vss adaptor to control the LS PCM.
The electronic one from the 90's was TBI. I cant remeber what year truck I got it from but is the 89-97 ish body style. The vortecs then were still tbi wither way.
Vortec (1996-2002) is CPFI. They were OBD2 trucks, which I have no idea if they had changed how cruise operated by then. I would expect they had. At some point I'd expect they integrated it into the PCM, but that may still be an option for you depending on how the LS-series ran cruise control. You know what the VSS requirement is, I'd tend to want to scrap anything I could off the "older" setups that required a buffer.
I don't know when the 1988+ C/K's stopped using the DRAC, but when they did, that may be when cruise changed. You'll have to do some investigation to see how cruise operated.
You might be too far into the parts already, but would the '90-91 cluster/NP241 setup (with it's 40 tooth reluctor VSS) make any sense in your case?
If I was swapping to an LS and the possibility existed to eliminate the speedometer cable and drive gears, cruise module/VSS buffer/and associated wiring, I would if it made financial sense, and if the 40 tooth VSS setup from the 241 provided what the LS PCM is looking for. Just a thought.
I don't know when the 1988+ C/K's stopped using the DRAC, but when they did, that may be when cruise changed. You'll have to do some investigation to see how cruise operated.
You might be too far into the parts already, but would the '90-91 cluster/NP241 setup (with it's 40 tooth reluctor VSS) make any sense in your case?
If I was swapping to an LS and the possibility existed to eliminate the speedometer cable and drive gears, cruise module/VSS buffer/and associated wiring, I would if it made financial sense, and if the 40 tooth VSS setup from the 241 provided what the LS PCM is looking for. Just a thought.
Bassically I am planning to follow this diagram. Instead of taking the VSS from the PCM can I just run directly from the sensor to the module or does the PCM provide a buffer?
I didn't spend a ton of time looking, but this says 4000PPM: http://lt1swap.com/wiringharness.htm which is double what our trucks had. But in thinking about it, the only "difference" in using that doubled signal is that you'd be able to engage cruise at 12.5MPH, instead of the lower threshold of 25MPH the cruise already has. But IMO who cares? I don't believe there is a speed at which you can't set cruise (not positive though) but if there was, that would be an issue. I've never heard of it, then again I doubt anyone has tried to set cruise at 140MPH in one of these trucks either.
If that diagram is from our vintage trucks, and your '87 is already wired for cruise, you shouldn't have to do any wiring but the wire(s) from the PCM to the correct terminal(s) on the cruise module. I'm assuming that diagram is correct on pinouts, etc., as I didn't actually look at my wiring diagram.
If that diagram is from our vintage trucks, and your '87 is already wired for cruise, you shouldn't have to do any wiring but the wire(s) from the PCM to the correct terminal(s) on the cruise module. I'm assuming that diagram is correct on pinouts, etc., as I didn't actually look at my wiring diagram.
Oook. Figured out why I was so confused. Kwpt thinking the pcm and vss was from the 87. Once I figured out that is from the lsx pcm (duh *facepalm*) its pretty easy / self explanatory.
Found my connector. Pretty cool setup for the time. Little printed circuit connector.
Found my connector. Pretty cool setup for the time. Little printed circuit connector.
Yep! They used really tiny connectors on those things.
So you are intending to essentially keep the cruise setup as-is, just changing the VSS input and to electronic cruise?
If you don't mind, I'd like to know what you find out about the electronic cruise motors and how to adapt to this setup. I was at a wrecking yard not too long ago, and saw plenty of the '88+ trucks with it, and I know S10's and F-bodies used them too, at least for awhile. Just don't know when/if things changed on them that would cause them not to work on our rigs.
About the only thing I know that changed on them was the cable length. Depending on application, some of them I saw were long enough to probably mount the cruise motor on the fender.
I don't recall what mine came off of (still vacuum) but mine is mounted on the auxiliary battery tray...that's quite a reach lol.
So you are intending to essentially keep the cruise setup as-is, just changing the VSS input and to electronic cruise?
If you don't mind, I'd like to know what you find out about the electronic cruise motors and how to adapt to this setup. I was at a wrecking yard not too long ago, and saw plenty of the '88+ trucks with it, and I know S10's and F-bodies used them too, at least for awhile. Just don't know when/if things changed on them that would cause them not to work on our rigs.
About the only thing I know that changed on them was the cable length. Depending on application, some of them I saw were long enough to probably mount the cruise motor on the fender.
I don't recall what mine came off of (still vacuum) but mine is mounted on the auxiliary battery tray...that's quite a reach lol.
If you have a TBI and want an almost plug and play setup, I am no longer going to use my factory setup, mounts, and all that stuff.
Obligatory three words.
Ahhh....thought the module in that hand drawn diagram was "our" stock one!
So the later setup integrated the cruise module into the motor housing? THAT I did not know...NOW it all makes sense.
Since I've got a DRAC, this swap is going to be easy. Wonder if the stock cruise wiring will reach to the engine bay/new module if it's removed from the stock wiring harness bundle?
So the later setup integrated the cruise module into the motor housing? THAT I did not know...NOW it all makes sense.
Since I've got a DRAC, this swap is going to be easy. Wonder if the stock cruise wiring will reach to the engine bay/new module if it's removed from the stock wiring harness bundle?
On mine it does not. My wires and plugs are totally different from the new setup so I have to do so soldiering anyways. Also when I pulled the cruse module I just clipped a pig tail for the new cruse module.
I've got to strip a bunch of unused wiring out of my under-dash wiring, was hoping GM had snaked the wires up from fuse panel/column up and over, adding a bunch of length to fit. Oh well.
I read that thread, didn't see any reason given why you couldn't use the ones with a plug in the H position. There are enough of these out there that it doesn't really matter, but curious as to what makes them so different.
Can you tell if this is the connector? http://www.electricalhub.com/media/...9eda06f020e43594a9c230972d/1/2/12065425_3.jpg It sure looks like it. I've got to place an order anyway, I've gotten to the point of just making the wires anymore instead of soldering where I can. I just haven't messed with the "newer" stuff enough yet to know what all connector series they are using. If there is a part number on the connector, that would help too. 12065425 would appear to be the right connector PN, FWIW.
Thanks!
I read that thread, didn't see any reason given why you couldn't use the ones with a plug in the H position. There are enough of these out there that it doesn't really matter, but curious as to what makes them so different.
Can you tell if this is the connector? http://www.electricalhub.com/media/...9eda06f020e43594a9c230972d/1/2/12065425_3.jpg It sure looks like it. I've got to place an order anyway, I've gotten to the point of just making the wires anymore instead of soldering where I can. I just haven't messed with the "newer" stuff enough yet to know what all connector series they are using. If there is a part number on the connector, that would help too. 12065425 would appear to be the right connector PN, FWIW.
Thanks!
They did I just dont believe it is long enough to do more than make it just past the bulkhead/firewall.
I got my module + pigtail and both cables for $15 at pull-a-part. I could not see a part number on the connector.
I assumed there could be a programming difference or something. I actually forgot to look before I bought mine and got lucky it didnt have a wire in the H terminal.
Where do you intend to mount yours? I noticed the C/K series at least fairly early on mounted them to the firewall pretty much right in front of the driver, but the cable on some of the setups is so long, you could mount it darn near anywhere you wanted.
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Have not decided yet. Probably closer to the pass side. I want to finish my swap and wiring to see where it all looks cleanly installed before I bolt it to the truck.
