wetskier2000

Hello Gentlemen..

I have swapped a 1999 LS1 from a C5 into a 1941 Ford cabover truck. It's running and driving using mostly all the stock Corvette parts. The harness, while stretched a bit is all stock, stock ECM, gauge cluster, column, etc... I have not installed any ABS, TC or ride control items. The ECM complains about these with idiot lights and the DIC. Would one of these missing systems also disable Cruise Control?

Cruise does not seem to work. I checked the ECM and BCM pinouts looking for something that might indicate the health of these systems to the ECM but found nothing. I suspect they communicate on the bus.

Is it possible to make cruise work w/o these systems in place?

garys 68

iTrader: (1)

A 99 corvette is DBW, correct?
If so, it should be built in. You should only need the additional brake light switch hookups and clutch pedal position switch (manual) along with a NO stalk or dash control.
A couple questions, is it manual or auto, and what trans?

wetskier2000

Yes.

That's what I was hoping for..

I think I have all of those in place. Both stock C5 brake pedal switches are installed and appear to be working. The button on Clutch Pedal UP switch is "safety wired" in the pushed in position. The Clutch Pedal DOWN switch is only used manually to start the engine. The multi-function stalk is in the stock column and working for other things like the headlights.

The Corvette was a 6 speed stick. The truck is now an early 1993 4L60E shifted by a cable and managed by the ECM. The ECM is not what was in the Corvette, instead it's a JY Silverado unit with the same number that was removed from the Corvette. (the corvette ECM had a tuner password we didn't know).

I had to add wiring for the 4L60E to the 6 speed Corvette harness. I just matched up the 4L60E pins to the pinouts on the ECM. The only wiring difference from the early unit to the 4L60E that would have been behind the LS1 in 1999 was PWM.

Thanks very much for the help!

Rick

garys 68

iTrader: (1)

It's probably a 411 ecu used in both cable and DBW. The DBW function with a TAC has the capability of running Cruise without BCM, etc in trucks.
There are some repins and rewire between DBW and cable (ie CPPS 12 vs ground) if the truck had cable TB. You also need to reset the ppm for manual vs trans. I suspect the issue is somewhere in your mix & match.

wetskier2000

I'm learning this as I go along, please bear with me.. I did not even think that the Silverado would not have been DBW.

It would be great if I only needed to rewire or repin a couple things.. I'm not familiar with PPM and CPPS acronyms. What do they stand for?

thanks again!

Rick

garys 68

iTrader: (1)

The 411 ecu was in vettes (all DBW), f body (all cable) and trucks (some DBW, some cable). I had an issue with a later ecu getting DBW CC to work when going from auto to manual trans with programming.
CPPS= clutch pedal position switch
PPM= pulse per mile, 17 vs 40 tooth speed sensor reluctor for auto vs manual trans

wetskier2000

Thanks for the clarification...

PPM is already set to 40 via EFI Live for the Speedo correction.

However, if Clutch Position (CPPS) is supposed to send ground for the Silverado when I'm pretty sure it's sending 12v for the Corvette, that sure could be the issue.

I think that switch is open and sends nothing to the ECM when the clutch is not depressed and sends 12+ when the clutch pedal is being pressed. Right? So in the Silverado it would have been Clutch Pedal Up=Open, Clutch depressed=GND?

thanks again!

wetskier2000

I see I never updated this thread! The issue with cruise control was that I did not have a 3rd brake light (CHMSL) in the circuit. Yeah, unbelievable, huh?

Next programming trick will be telling the transplanted LS1 to forget about ride control, etc so I can get rid of the 80 MPH restriction. Anyone done this?