CTIS Cold weather operation

[Skyhawk13205]

I am up in Alaska, I been having trouble with my truck CTIS system draining all the tyres after shutdown.

I did some troubleshooting and all the wheel valves stay open, after the CTIS ecu does a pressure check. I can go through and manually close them and they stay closed. My CTIS works well in temps above 20 deg.

It is pretty cold about 0 deg tonight. I have been running the eco hubs so the hubs don’t get really hot.

I looked though the operators manual and it makes mention of a CTIS off switch operation during cold weather operation until wheels are up to temp


I have used CTIS on/off switch, but all it seems to do is turn on the indicator and does not deactivate the ECU. It looks like the switch is jumpered per the wiring diagram. See line 501/502


What is the purpose of this switch? Does it jumper a program pin that is not listed in the wiring diagram? Am I missing something? I would like the ability to deactivate my CTIS per the engineered intention vs disconnecting the ECU.
Thanks.

 

[Keith Knight]

I installed this switch 8 months ago on a different thread.

 

[Keith Knight]

Found the thread look on page 15 of the thread.

 

[Skyhawk13205]

I installed this switch 8 months ago on a different thread.

Thank you, I appreciate it. Looks like you wired in a switch. Did you wire in the switch at p111 disconnect?

 

[Keith Knight]

The switch is circled in red on the schematic.

 

[GeneralDisorder]

In cold weather you have to manually vent the wheel valves or they can leak and not hold pressure - remove the screws from the wheel valve covers.

If the valves are in good condition they generally work down to below 0 degrees. But old diaphragms may be adversely affected at higher temps due to old rubber and poor sealing.

 

[Skyhawk13205]

I installed this switch 8 months ago on a different thread.

Thank Keith, I found the jumper wire and disconnected it, now the CTIS ECU powers off with the CTIS off switch. It must be an instruction to disconnect in the Arctic kit install but just was not done.

 

[Skyhawk13205]

In cold weather you have to manually vent the wheel valves or they can leak and not hold pressure - remove the screws from the wheel valve covers.

If the valves are in good condition they generally work down to below 0 degrees. But old diaphragms may be adversely affected at higher temps due to old rubber and poor sealing.

Thanks for the info, I opened up my wheel valves and they have some corrosion, I think they are leaking across the diaphragm. When I take the vent screws out to manual shut the valves I do hear air ecasping. I ordered some rebuild kits from colt, hopefully they fix my issue and I can use my CTIS below 20deg.