viper 5901 works great but cruise stopped

Evening all! A few months back I successfully installed a Viper 5901 in my Girlfriends car, a 2005 Chevy Equinox. The Viper works great but we lost the cruise control function when I did the install. There are no lights or any indication of the cruise being operational when you press the buttons on the steering wheel at highways speeds. Scheduling to work on it has been really hard. I started to dig into it at one point, looking for obvious stuff, fusses, forgotten wiring harness connector, etc… but ran out of time. I’m going to have it again this weekend and looking for any tips to start troubleshooting or if this might be a common rookie mistake that someone has a quick fix for. I decided to use the resistor/relay setup instead of a bypass module. I did diode isolate a lot of the wires but don’t remember specifically if I did the brake light. With the research I’ve done so far I’m starting to think it might be something related to the brake switch circuit. Any tips or suggestions from the pros would be greatly appreciated to help me be as prepared as possible once I get my hands on it. Thank you! Randy

Ughh. I had "in 05 Chevy Equinox" at the end of the Topic but somehow it was cut off and I'm not able to edit that. Sorry for the inconvenience.

What did you diode isolate? the only thing you would need to diode isolate on that car would be the door triggers. If you used diodes anywhere else take them out as they arent needed and could be causing your issues. I have an 05 Equinox myself and a Clifford 1.3x with smart start, the whole shebang and no diodes anywhere.

It was the door triggers, three or four if I remember correctly. Seemed like there was more but I can't remember for sure. Haven't had time to pull my documentation of the install out yet. I'll check that when I get it apart. I think the first thing i'm going to try after another good visual inspection is disabling the unit and disconnecting the brake wire. My gut is telling me it's either coincidental or something stupid. Did you have to interface with the brake switch circuit or is that part of the smart start? When I planed this install I heard a lot of people complaining about the bypass modules having problems and the two relay bypass has been proven stabil. Additional relays and a little more wiring but I wanted reliability over convenience and it was a lot cheaper since I had the relays and resistors sitting on the shelf although I really HATED having to cut the wire at the key switch. All connection were soldered, heat shrunk or taped and wire tied.

The smart start is just an add on to the remote start system. Does the orange light come on on the button on the left side of the wheel at all. If not I don't think it is a brake issue. I would check all the harnesses going into the column and make sure all is tight. Did you unplug any connectors at the BCM? Id check them too.

Check your brake light connections, also clutch switch if a manual though the fact that the light doesn't come on suggests an unrelated power supply problem.

disconnect the brake wire from the RS, take it for a drive and see if the cruise will turn on.  If not, you may have to recheck fuses. DONT forget the fusebox under the hood.