Threw a P1875 code today?

[IRQVET]

Towed my trailer to the race track, truck drove fine but about half way there my Service 4WD light came on. Never seen that idiot light before. Looked down and noticed the lights on the push button 4WD was not lighted up.

Got to the track and scanned the computer, got two codes:

P1875 code- 4WD Low Switch Circuit Electrical
P0140 code- HOS2 Circuit Insufficent

On the drive home, the truck was sputtering off the line at slow speeds, but drove normally after that.

I recently as of 2 months ago replaced my 4WD control module.

The P0140 I’m assuming is because I removed my cats and the 02 censors are currently disconnected.

You guys are experts, so any input is appreciated . . .

 

[east302]

The GM manual has the diagnostic for the code, here are the pages for P1875. I’d agree that the catalyst code could be disregarded if it was there before these symptoms appeared. The rest of the manuals (four volumes) can be downloaded here:

88-98 Service Manuals

Over the years I have collected a bunch of GM service literature. Links to PDF Scans of service and STG manuals and a links to the Parts manuals. You'll need the FREE Adobe Acrobat reader to open these files. Get it directly from Adobe here {http://get.adobe.com/reader/} If you're not...

www.gmt400.com

 

[OR VietVet]

I would assume that an inspection of all connections is warranted, especially at the 4wd module. Any other work done in the last 2 months?

 

[IRQVET]

No other work done. What had happen was I had a parasitic draw on the electrical system. Had a clicking noise that sounded just like the turn signal was on. Reached my hand under steering shaft and found the clicking noise and vibration was coming from my 4WD control module. So I replaced it two months ago, and the noise and draw went away.

Then this happen.