'11 silverado, python 872

I've installed the 872 remote start/keyless entry over a year ago but just cant seem to get it to work correctly. It'll start fine if the vehicle is warm, but never if it's been sitting for more than an hour or so. It will crank and catch, sometime almost run but shuts right down. Sometimes it sounds like a starter haning up. On a couple occasions it will try and start but then crank continuously, with no fire, till I shut it down. Thats only happened a couple times though. I'm using the xpresskey with a key in the box for the bypass.   
I've tried the various options for increasing crank time and using different methods for vehicle monitoring (Virtual crank, Voltage, and Tach). It starts most reliably with Voltage but shuts itself off after a few seconds to a few minutes. I've tried using the injector trigger and the coil trigger for the tach. signal. Both with identical results. I have tried tach learn under various conditions. (i.e. Cold, warm, after sitting for a weekend etc.)
The vehicle is a 2011 Chevy Silverado 1500 WT. It did not come with power door locks, cruise or power windows, all of which I have installed.
Any input is appreciated.

I would run a diagnostic check to see what the Python is thinking is shutting down the cycle.

Also, you stated you used the xpresskit with the key in the box. What module (if any) are you using to control the starter and 2nd starter wire?

If you start the truck with key and then press the remote start button, can you remove the key and the truck stay running?



-------------

Are you getting any type of security light? I know using the key in a box is pretty straight forward with firing up the ignition and accessory wires.. Done many of these trucks that way, especially the work truck packages...Did you see how it acts if you keep the key in the ignition???

If I start it with the key and press the remote start button the truck continues to run with the key removed. If I leave the key in the ignition and push the remote start button it just cranks continuously with out starting. I don't get any security lights or error messages.
I forget which key in a box kit it is. I think its just called the Tbxkey. Is there a part number on the box or something that will divulge more information?

Tbxkey is a universal key in a box solution. I've used them before.

It doesn't sound like a security or bypass issue since you are using a genuine key in a box. Even when you leave the key in the ignition switch and try remote starting, it just cranks and cranks.

The starter, accessory and keysense uses the same mux wire.   How did you connect that wire? With a module? Relays? Resistors? Other?

Do you have a tach wire connected and performed tach learning on the remote starter?



-------------

I did not use any module, other than the 872 module itself, or resistors or relays to conect to the keysense, starter, acc wires. It's been a while so I can't remember how it all hooks up but I used informaion from this site for specifics on installation as well as this info:

https://www.bulldogsecurity.com/bdnew/vehiclewiringdiagrams.asp

If need be I can get the wire colors as its hooked up now.

The tach wire is currently hooked up to the coil primary wire. I have also had it connected to the injector trigger wire. I have performed the tach learn sequence under many different conditions; when the vehicle is warm, when it is cold, when it's been sitting for an hour and after a weekend of sitting, none of which has allowed it to start reliably. It will start using the voltage sense feature but will usally shut down after a few minutes.
Shortcircuit161, you mention a diagnostic check on the unit. Is that something I can do to elicit a series of beebs or blinks that corespond to a trouble code of sorts? That would be amazingly helpful if thats the case!

To perform shutdown diagnostics:
1. With the ignition Off, press and hold the Control button (on Control Center).
2. Turn the ignition On and then back Off while holding the Control button.
3. Release the Control button.
4. Press and release the Control button. The status LED flashes to report the last shutdown for one minute or
until the ignition is turned on, as shown in the following table:

Status LED Flashes Shutdown Mode
1 flash Runtime expired
2 flashes Over-rev shutdown
3 flashes Low or no RPM
4 flashes Transmitter shutdown (or optional push button)
5 flashes (+) Brake shutdown
6 flashes (-) Hood shutdown
7 flashes Timer mode/Turbo mode/Manual mode error *
8 flashes Neutral safety shutdown
9 flashes Low battery (voltage mode)
10 flashes Alarm triggered **
11 flashes Wait-to-start input timed out
* Timer mode error: Ignition is on or shutdown input is active when activating timer mode.
Turbo mode error: Turbo mode is programmed off, engine is not on or shutdown input is active.
Manual mode error: MTS mode not enabled.
** Alarm was triggered during remote start sequence.

-------------

The "Control Center" is the main black box correct? I don't see a button or light on it. Do I need to open it up?

The point may be moot though. On the third attempt of the the starting cycle it just cranks and cranks without starting and I have to shut it down with the remote to stop it. I'm sure if it flags a code it would be that last trigger, being shut down via the remote.

The continuous crank with no start on the third cycle is new as of today. It has never done that before and I haven't changed any of the settings.
It should be noted that this unit is a factory refurb.

Just looked up diagnostics in the manual. It's the Valet switch. Sorry for being obtuse.
I also see a jumper listed for changing the tach threshold. Is that something I should be cognizent of or just ignor it and leave it off?

Cranking and cranking sounds like a tach learn issue but there are other things that could cause it too (such as incorrect or loose wiring somewhere).

Yes, the "control center" is the antenna/LED/valet button.

I wouldn't mess with the tach threshold jumper. I believe it's defaulted to high.

I usually go direct to a fuel injector for tach signal. There is usually one wire that's the same color for all injectors on that side of the engine. You want to use the other wire on that injector.



-------------

The 2011 Silverado should a Passkey3+ system which is a hybrid transponder and Passlock type setup. So not only is the ECU looking for the transponder code, it is looking for a change in voltage on the PL wire. The constant cranking is most likely the result of not getting the correct PL voltage.
The PL wire voltage will vary according to the following:
On keysense is +/- 12V
On accessory is +/- 0V
On ignition is +/- 4V
On start is +/- 3V
You can try to replicate these values with relays and resistors but it would be easier to use a module for this task.

I have been using the OL-MDB-AL (ADS-AL-CA) or Fortin EVO-ALL whenever I encounter PK3+ systems. You can keep the TBxKey with XpressKey and not wire up the transponder portion of the ADS or Fortin modules as shown in the install guide.

-------------
This information is provided only as a reference.
All circuits should be verified with a digital multi-meter prior to making any connections.

That makes sense. But why does it work when I use voltage sense instead of virtual tach? Also why does it only crank continuously on the third attempt per cycle? And why does it function perfectly if the vehicle is warm?
It also appears that some people have used the tbxkey sucessfully on similar vehicles. I will try one of those modules you mention though and see how it works. Thank you for the input.

Did you ever get your truck to start? Also, I am thinking about installing power locks, mirrors, and windows in my 2011 WT. Can you tell me what kits, parts you used to do thisto your truck. I also want to put a remote start in.

Thanks...

Wow, I just happened to check on my old post since I only recently found the time to work on the truck and somebody else had revived it. In short, no, I have not gotten the truck to start with the remote start. I picked up a Fortin Evo-All CANBUS module but all it does is make the truck think there is a key in the ignition all the time.

Here is a link to the power window kit I bought from Amazon:

https://www.amazon.com/Absolute-HW600-Power-Window-Conversion/dp/B004IX6798/ref=sr_1_2?ie=UTF8&qid=1369602854&sr=8-2&keywords=power+window+kit

The switches fit right over the holes left by the cranks once you open up the holes a little. They could use more power though, the passenger side only works if the engine is running. Theres probably better kits out there.
The locks I pieced together with a bunch of parts from eBay and stuff I had laying around. I thought about putting in power mirrors but I have the manual towing mirrors and they've been fine.
And a word of advice, don't buy a factory refurbished Directed Electronics product. I'm pretty sure that's why I'm having all these problems with getting this thing to work.