DBW 6.0 in an 84 and cruise control

[superdav]

Maybe I missed it but the only thread I could find using the OEM switch was using a DBC. I just got a 2003 Denali donor vehicle DBW and I want to keep my OEM switch (84 Silverado), do I have to switch to DBC?

ETA Im going to start stripping the Denali soon and part it out but I want to make sure I get all the parts I need before I get rid of it and not sell the parts I do need.

[68c10airstream]

I did a dbc for my 2001 5.3 and that uses a remote box/cable assembly to pull a cruise cable that sits right next to the throttle cable.

What little i know about cruise in a dbw system is i believe you are just sending voltage signals from the stalk switch to the tac (throttle actuated control??) module. Your dbw gas pedal works with the tac module to then send the commanded signal to the throttle body.

You will need to keep your gas pedal, tac module, and rob the cruise stalk switch. Get with LS1 nova on this forum as he mods the cruise switches to work with what ever you want to run and has a full write up on your dbw cruise layout. Good luck!!

P.S. eric(LS1NOVA) is a fantastic help on this stuff!

[Clyde65]

Here is The setup. Has DBC and DBW info.
http://67-72chevytrucks.com/vboard/s...d.php?t=511477

[ls1nova71]

Originally Posted by superdav

Maybe I missed it but the only thread I could find using the OEM switch was using a DBC. I just got a 2003 Denali donor vehicle DBW and I want to keep my OEM switch (84 Silverado), do I have to switch to DBC?

ETA Im going to start stripping the Denali soon and part it out but I want to make sure I get all the parts I need before I get rid of it and not sell the parts I do need.

The cruise on a DBW set up is super easy, and in your case with a factory GM switch, even easier. You're going to need the PCM, TAC and pedal to make the engine run anyway, I'm sure you knew that, so there isn't anything else specific to cruise control you'll need off the donor.

To hook up the cruise, you'll need to hook up both brake switch wires, one will be hot when the brakes are not applied and goes to pin 33 on the C1 connector, it will be a purple wire, the other will be hot with the brakes applied and goes to a light blue wire on pin 6 of the TAC module plug C1.

To hook up the switch, you will need to hook up 3 wires under the dash where the column plugs are. The cruise plug has 4 wires in it, the pink one is the ignition power and you should be able to leave that one alone since it will already be hooked to power. The others are, blue, green and gray. The blue one is the set/coast wire and will go to the TAC module plug C1, pin 4 and will be a dark blue wire, the green is resume/accel and goes to TAC plug C1 pin 5 and will likely be gray with a black stripe. The last one is the on/off and will go to TAC plug C1 pin 14 and should be a gray wire.

Hope this helps. Let me know if you need any clarification on anything.

[superdav]

Originally Posted by ls1nova71

The cruise on a DBW set up is super easy, and in your case with a factory GM switch, even easier. You're going to need the PCM, TAC and pedal to mak...........

Sweet! Thanks for the info everybody else too!

[cru_zn_29]

Originally Posted by ls1nova71

The cruise on a DBW set up is super easy, and in your case with a factory GM switch, even easier. You're going to need the PCM, TAC and pedal to make the engine run anyway, I'm sure you knew that, so there isn't anything else specific to cruise control you'll need off the donor.

To hook up the cruise, you'll need to hook up both brake switch wires, one will be hot when the brakes are not applied and goes to pin 33 on the C1 connector, it will be a purple wire, the other will be hot with the brakes applied and goes to a light blue wire on pin 6 of the TAC module plug C1.

To hook up the switch, you will need to hook up 3 wires under the dash where the column plugs are. The cruise plug has 4 wires in it, the pink one is the ignition power and you should be able to leave that one alone since it will already be hooked to power. The others are, blue, green and gray. The blue one is the set/coast wire and will go to the TAC module plug C1, pin 4 and will be a dark blue wire, the green is resume/accel and goes to TAC plug C1 pin 5 and will likely be gray with a black stripe. The last one is the on/off and will go to TAC plug C1 pin 14 and should be a gray wire.

Hope this helps. Let me know if you need any clarification on anything.

Hi I have a 1966 c10 with Gen IV 5.3 4L80 and trying to get cruise control working correctly. I have a kit from Rostra 250-1848 with cruise switch #250-3020-EC. After installing the the cruise will in gauge say 45mph then it surges if i speed up to 60 then it goes wide open. I have called the supplier he says i have a dirty signal. Do you know how i can fix this

[68c10airstream]

The vss (vehicle speed sensor) could possibly have a few specks of metal stuck to the face of it, giving a vague signal with less definition because the face has ultimately been widened. I'm assuming this vss is mounted onto the extension housing. Just remove, inspect and clean the face. If there is a lot of stuff on the face it could mean a bearing is failing or other problems possible. This is easy to pull out for inspection. Just do it for peace of mind and have it off the check list. Good luck!!

[cru_zn_29]

Thanks I will try that.

[68c10airstream]

I looked into your rostra kit install and basically you added an additional cruise system onto a gm system ready for cruise control. Not to shoot down what you did but ls1 nova summed up the gm system uses the tac module and the location to plug the cruise stalk switch into.

Another words, if you didn't own the rostra kit, all you basically need is a stalk switch to be added and wired into the tac module. The stalk switch is just sending a voltage signal to the tac module. The tac module sees this signal and says "i'm going to take over and run the throttle based on vehicle speed and ignore the gas pedal unless you step on the gas to accelerate".

Being that you already installed the rostra system i believe you could just wire the stalk switch directly to the tac module.

Not to complicate things for you but as i devote a little gray matter to this the rostra system is putting another throttle signal onto the existing throttle circuits. The beauty with the gm system is the engineers will modify the throttle response based on what is called r.o.c. This stands for "rate of change". As an example; say you are using the gm cruise at 60 mph in overdrive and it's coming to a hill the system will see how fast the set speed is dropping and the rate of drop and will accelerate at an appropriate rate, working with the trans shifts, and unlocking the torque converter.

I believe the rostra system responds in a different manner in the above example. I would be hard pressed to believe an aftermarket system added in parallel to an existing gm system will work as well. I do believe newer accessories work substantially better than they did in the past!

I can also look at this with a different mindset, a room full of gm engineers have to develop a system that has built in safety redundancy, fuel efficient, satisfy customers, be integrated into existing systems,and keep costs reasonable.

In defense of the aftermarket, we wouldn't be where we are at with all of these swaps without them, a delicate balance.

[ls1nova71]

Originally Posted by cru_zn_29

Hi I have a 1966 c10 with Gen IV 5.3 4L80 and trying to get cruise control working correctly. I have a kit from Rostra 250-1848 with cruise switch #250-3020-EC. After installing the the cruise will in gauge say 45mph then it surges if i speed up to 60 then it goes wide open. I have called the supplier he says i have a dirty signal. Do you know how i can fix this

Those aftermarket cruise controls seem to be hit or miss. Some people hook them up and they work perfect, others not so much, even with the exact same one. What are you using for a speed signal? I have heard there is a magnetic pick up type that goes on the driveshaft that is supposed to work when you cant get a decent speed signal, but I have never personally tried it.

Originally Posted by 68c10airstream

I looked into your rostra kit install and basically you added an additional cruise system onto a gm system ready for cruise control. Not to shoot down what you did but ls1 nova summed up the gm system uses the tac module and the location to plug the cruise stalk switch into.

Another words, if you didn't own the rostra kit, all you basically need is a stalk switch to be added and wired into the tac module. The stalk switch is just sending a voltage signal to the tac module. The tac module sees this signal and says "i'm going to take over and run the throttle based on vehicle speed and ignore the gas pedal unless you step on the gas to accelerate".

Being that you already installed the rostra system i believe you could just wire the stalk switch directly to the tac module.

Not to complicate things for you but as i devote a little gray matter to this the rostra system is putting another throttle signal onto the existing throttle circuits. The beauty with the gm system is the engineers will modify the throttle response based on what is called r.o.c. This stands for "rate of change". As an example; say you are using the gm cruise at 60 mph in overdrive and it's coming to a hill the system will see how fast the set speed is dropping and the rate of drop and will accelerate at an appropriate rate, working with the trans shifts, and unlocking the torque converter.

I believe the rostra system responds in a different manner in the above example. I would be hard pressed to believe an aftermarket system added in parallel to an existing gm system will work as well. I do believe newer accessories work substantially better than they did in the past!

I can also look at this with a different mindset, a room full of gm engineers have to develop a system that has built in safety redundancy, fuel efficient, satisfy customers, be integrated into existing systems,and keep costs reasonable.

In defense of the aftermarket, we wouldn't be where we are at with all of these swaps without them, a delicate balance.

GenIV engines don't have a TAC module, and are completely different when it comes to cruise control. It's one of the down sides to the newer engines...

[homemade87]

Originally Posted by ls1nova71

Those aftermarket cruise controls seem to be hit or miss. Some people hook them up and they work perfect, others not so much, even with the exact same one. What are you using for a speed signal? I have heard there is a magnetic pick up type that goes on the driveshaft that is supposed to work when you cant get a decent speed signal, but I have never personally tried it.



GenIV engines don't have a TAC module, and are completely different when it comes to cruise control. It's one of the down sides to the newer engines...

I see where people are hooking to the tac module to get cruise . I have a 04 truck system I have hooked cruise to . I did not attach to the tac . I only used the pcm wires to get cruise to work . I am sure there is different ways to do it but mine works perfect . I would think you could do this as well with the newer systems with out the tac .

The OP could do either one pretty easy and solve the problem along with the required power and brake switch as ls1nova has stated above . Also I think the 84 has the required 4 wire switch it takes to make it work which will make it easier . Mine was a 82 and I had to modify a switch .

[ls1nova71]

Originally Posted by homemade87

I see where people are hooking to the tac module to get cruise . I have a 04 truck system I have hooked cruise to . I did not attach to the tac . I only used the pcm wires to get cruise to work . I am sure there is different ways to do it but mine works perfect . I would think you could do this as well with the newer systems with out the tac .

The OP could do either one pretty easy and solve the problem along with the required power and brake switch as ls1nova has stated above . Also I think the 84 has the required 4 wire switch it takes to make it work which will make it easier . Mine was a 82 and I had to modify a switch .

I'm curious, what wires did you hook up the switch to on the PCM to make it work? I have never heard of anyone doing it that way.

[superdav]

Originally Posted by homemade87

.......... Also I think the 84 has the required 4 wire switch it takes to make it work which will make it easier........

yes and I even have brand new still in the box OEM one I paid $2 for about 10 years ago at a local warehouse type store that sold overstock and return type stuff that since closed

[homemade87]

Originally Posted by ls1nova71

I'm curious, what wires did you hook up the switch to on the PCM to make it work? I have never heard of anyone doing it that way.

Ok , after looking at what I did I used/reworked my factory harness and the C100 connector under the hood had the cruise wires in it that I used .

C100 - I/P Harness to Engine Harness
Pin Wire Color Circuit No. Function
A DK BLU 84 Cruise Control Set/Coast Switch Signal (KUP)
LT BLU/BLK 396 Cruise Control Engaged Signal (w/o KUP)
B GRY 48 CPP Switch Signal (ML6, MG5 )
C BRN 241 Ignition 3 Voltage (TP2)
D DK GRN/WHT 817 Vehicle Speed Signal
E DK BLU 507 Wait to Start Indicator Control (Diesel)
F -- -- Not Used
G BRN/WHT 419 MIL Control
H DK GRN 1049 PCM Class 2 Serial Data
J BLK/WHT 5668 Engine ON Signal (SBA)
K WHT 121 Engine Speed Signal
L GRY 397 Cruise Control ON Switch Signal (K34)
M YEL 710 Class 2 Serial Data
N BRN 241 Ignition 3 Voltage (NP1, NP2, and NP8)
P DK BLU 204 A/C Low Pressure Sensor Signal (CJ2/CJ3)
R YEL 2470 Class 2 Serial Data (M74)
S GRY/BLK 87 Cruise Control Resume/Accel Switch Signal

I am now not sure if the cruise wires go to the tack or to the pcm . I had assumed they went to the pcm . If someone has an 04 truck wiring diagram to verify , that would be helpful . LT1swaps.com is where I got this info I used .

[cru_zn_29]

I used pin 41 on the TCM for speed signal. The reason i ordered the Rostra system because i could not get any info on Gen IV system.The kit i ordered was for 2008 silverado for GEN IV. I did not want to use the Magnetic pickup type on the drive shaft.

[homemade87]

Originally Posted by ls1nova71

I'm curious, what wires did you hook up the switch to on the PCM to make it work? I have never heard of anyone doing it that way.

Well , it looks like I may have miss spoke . The wires in the stock harness appears to route themselves thru the harness and do not go to the pcm like I thought . This info here seems to to show they do go to the tac like ls1nova had stated . http://lt1swap.com/dbw.htm .