cajundragger

iTrader: (2)

I have a 1999 vette LS1 in a 1949 Chevy Pickup. It has a 2004 SSR 6 speed. I been driving the truck for about 2 years and I want to make the cruise work. Everything is DBW. I have a '99 pedal and a '99 TAC. I hooked up the clutch switch wire to +12 all the time, the purple wire to +12 all the time(not sure if I need this one?), the light blue is hooked to the brake lights getting +12 when pedal is moved and grounded though lights when not, cruse on is hooked to a on/off switch that gives it +12 and the accel/set wires are hooked to a on/off/on switch and each wire is getting +12.

I checked everything with my Tech2 and I am getting signals the the clutch is disengaged, the brakes are disengaged but I can engage them when the pedal is depressed, and that cruise is turned on. I also get signals that I can turn on the set and accel functions. Everything seems to be working on the tech2 but no matter what cruise request always says no and I can't get cruise to work.

Does the ecm have to see the clutch pedal cycle disengaged/engaged/disengaged?

Am I confusing the ecm by having the purple wire hooked to +12?

Im getting so aggravated by this and I can't figure it out to save my life. I have efilive, a tech2, and any other equipment I could possibly need, and everything points in the direction that it should work, but it doesn't.

Any help is appreciated, Im almost willing to pay a "finders" fee for anyone who can lead me right to my problem. haha.

Thanks guys.

LSXCESS

I am not sure which purple wire you are referring to. The only purple wires I see on the diagram are APP2 ground and TPS1 Ground. If you are powering up one of these this would obviously be a problem but you would also not be able to accelerate if you were.

1999 Corvettes have ABS and one of the things that can inhibit cruise is if the ABS is activated for more than 2 seconds. ABS codes will also inhibit cruise. I have seen LED taillights inhibit cruise before. I never figured that one out but the cruise worked with factory taillights.

It sounds like everything is correct on your inputs with the exception of that purple wire. I cannot find a purple wire relating to the TAC, Throttle body or anything cruise related other than the 2 that go into the TAC that are ground outputs to the pedal and TPS.

Could cruise have been accidentally disabled in the tune?

cajundragger

iTrader: (2)

purple is the TCC lockup. I figured I didnt need it since Im a manual but I hooked it up anyways just to see if it made it work.

Im not aware that the cruise is turned off but I will check right now.

I will check for any kind of ABS faults. Thats a good idea.

Thanks.

cajundragger

iTrader: (2)

I can't even figure out how to turn on or off cruise in efilive....

I do have LED tailights BUT I have temp wired in two bulbs to act as stock taillights. Once I get it working I will replace these with resistors.

From what I have figured from what I've read, the resistence to ground scales(gains) an amp somewhere. When that resistence is zero, there is no gain.

Im about to go back to the shop and check ABS faults on the way to tonights cruise night.

cajundragger

iTrader: (2)

I checked everything I could. I can't figure this out. help!

ls1nova71

iTrader: (4)

If you have a 6 speed then you dont need the purple wire, I'd unhook it. And I don't have a Corvette schematic handy, but on an F-body, the clutch switch goes to ground. Are you sure your schematic shows it needing 12v?

cajundragger

iTrader: (2)

I will check. Thanks.

Unhooking the purple wire is the only thing I can think of. Im real sure I have the clutch wire going to +12, I know on the tech2 Im getting a reading of disengaged clutch so I assume it to be working.

ls1nova71

iTrader: (4)

I had an issue once where I put power to a wire that was supposed to go to ground and my Tech II showed it to be working also. My problem was I didn't have any brake lights at all (No bed on truck) and was checking things with the Tech II and it showde the brake switches to be one engaged and one disengaged, putting power to it showed both disengaged, but when I wired brake lights up, grounding the wire made it show disengaged. I hope that makes sense. Might try grounding the clutch wire and see.

cajundragger

iTrader: (2)

will do, thanks! Im going right now to check, I'll report back.

cajundragger

iTrader: (2)

I have pin 33,35 and 62 all going to +12. That would be TCC, Clutch, and Extended brake travel. Any of this correct?

Im about to go check grounding each wire and see what happens.

ls1nova71

iTrader: (4)

Ok, the purple wire on 33 you DO need, I wasn't thinking that was the wire you were refering to. As for the others, I'm not sure, I don't have a Corvette schematic, but I'm thinking 35 needs to go to ground. Is that your only clutch pedal switch wiring? Or do you have a gray wire on 32 that goes to the clutch?

cajundragger

iTrader: (2)

I just check grounding each pin and watching the tech2, but got nothing. Its seems like each of those 3 inputs want +12.

Also, my tech2 calls the TCC wire, CC brake switch, which I assume to be cruise control brake switch.

Im also assuming for cruise to work I want ...

CC Brake Switch- Released
Clutch- Released
Extended Brake switch- released
Stop Lamp switch- released

I wonder if the ECM wants to see all these varibles change between +12 and GND because I am hooking them straight to +12 all the time.

cajundragger

iTrader: (2)

my harness was very incomplete. I had to add wires to control pins 33,35, and 62. If there is supposed to be a wire @ 32 I dont have one and my wiring diagrams I have show that pin 32 gets some kind of park signal which doesnt make sence because I have a M6.


I think my wiring diagrams suck. Im using OnDemand5.

aknovaman

iTrader: (7)

Your answer may be here:
Per http://www.lt1swap.com/dbw.htm


Drive By Wire = Electric motor controlling throttle blades. Gas pedal is a sensor, that feeds to a TAC Module (Throttle Actuator Control) The TAC module monitors the gas pedal sensor, then commands the throttle body motor to set the desired throttle setting. The TAC module also communicates with the PCM. Without this communication, the TAC module will not operate the throttle blade, and will cause codes to set in the PCM.

DBW was found on all Corvette's starting in 1997. Some higher end SUV's around 2001 started getting DBW. In 2003 all Pickup Trucks got DBW. In 2004 the Express Van got DBW.

If you are getting a motor from a salvage yard, be sure to get the Gas Pedal Assembly, TAC Module, and harness that runs from gas pedal to TAC module. It's a short harness, with a rubber grommet where it passes through the firewall. The rest of the wiring is part of the engine harness.

Wiring Schematics - Typical 2004 C/K Pickup 4.8 / 5.3 / 6.0




DBW - 1 of 2


DBW - 2 of 2


CRUISE - 1 of 2


CRUISE - 2 of 2




Okay, The important thing you need to know about wiring for this if you are modifying you're harness you're self. Very little needs done. 12v+ Key power to the PINK that feeds to the TAC module. This goes to the large black C2 connector that originally went into bottom of the fuse block. See here for C2 Info.

CRUISE CONTROL WIRING INFO

If you pull up the picture above DBW - 2 of 2, and look at the 4 wires in the upper right. These are for CRUISE. Three of these wires go to the C100 connector. One goes to the C2 connector.


C100 - A - DK BLUE - Cruise Set/Coast Signal

C100 - L - GRAY - Cruise On Signal

C100 - S - GRAY/BLK - Cruise Resume/Accel Signal

C2 - A10 - LT BLUE - Stop Lamp Supply Voltage/CHMSL (center high mounted stop lamp)





Cruise Set/Coast Signal - This is a momentary switch signal which sends 12v+ down this wire. Momentary meaning, it only sends 12v+ when the switch is pressed, when you release the switch, it should turn off. Pressing this switch quickly will set the current speed and it will be maintained. Holding it on will let vehicle coast, when you release, that will be the new set speed to be maintained. After set, each quick press of the switch will lower set speed 1 mph.

Cruise On Signal - This is simply an on / off switch that enables or disables the cruise function. This needs to be switched 12v+ to this wire.

Cruise Resume/Accel Signal - This is a momentary switch signal which sends 12v+ down this wire. Momentary meaning, it only sends 12v+ when the switch is pressed, when you release the switch, it should turn off. This switch ONLY functions after you have previously pressed the SET/COAST switch. Resume will resume vehicle speed after hitting the brakes. Holding this switch will make vehicle accelerate until you release it. Each quick press of the switch will increase set speed 1 mph.

Stop Lamp Supply Voltage - This wire should be hooked to the same wire that feeds you're brake lights 12v+ when you press on the brake pedal. THIS IS NOT THE SAME WIRE AS TCC BRAKE SWITCH THAT THE PCM USES TO UNLOCK TORQUE CONVERTER.

After those are wired, you also MUST have the TCC brake switch signal to the PCM. If this signal is not received by the PCM, cruise will not function. TCC Brake Switch Signal is 12v+ when brakes are NOT pressed, and the switch OPENS when you hit the brakes. This signal wire is at PCM connector C1-Blue: Pin #33; Purple wire.

ls1nova71

iTrader: (4)

This is correct, I'm still searching for what I'm looking for. I'll let you know when I find it.

ls1nova71

iTrader: (4)

THis sounds like a possibility, it may need to see 12v and also open.

ls1nova71

iTrader: (4)

Hey Anthony, I checked there, but the Corvette is different. I'm only finding the clutch wiring to be on 32, where as his is on 35 which on an F body goes to the PNP switch.

Do you have a schematic for a '99 Vette?

cajundragger

iTrader: (2)

so we have an '02 vette in the shop and for giggles I scanned it. It doesnt have anywhere on the tech2 where is lists if the TCC wire is doing anything. It seems like my truck has the wrong tune it and it wants an auto or something? but Im not throwing any codes so ? Im thinking about reflashing it with a known good '99 vette tune for a m6.

cajundragger

iTrader: (2)

scroll to the bottom of this and thats the exact diagrams I have.

https://ls1tech.com/forums/conversio...-diagrams.html

cajundragger

iTrader: (2)

I guess I should ask, what is different between 99 and 02, does 02 not have a TCC wire?