[Boss 429]

I recently bought a 2012 sel focus it was wrecked and I had to replace the entire front. got it running and a/c working when the cooling fans stopped and had all types of warning lights but motor stayed running, after i shut it down it wouldn't restart but I got engine malfunction waring. the only code I can get is 0850 and the display doesn't show the correct gear selection on the dash. I jumped the starter relay and it cranks. I found a shorted wire on the a/c compressor, fixed it and swapped out tcu ecu, no change. how do you clear the engine malfunction, any idea what could be wrong. or do I have to bite the bullet and take it to the dealer?

 

[Marde]

Do not think I can help much because I have zero experience with the 2012 type cars... but start with disconnecting the battery for 15 minutes. -and maybe re-install the original tcu and ecu. Changing tcu/ecu can cause problems unless done with care and some PATS keys programming.

 

[Boss 429]

I put the original tcm and ecm back in the dtc code says trans miscompare but I changed out the switch that sends the signal to the tcm which also sends a signal to the bcm for the trans position on the dash, I am thinking if it thinks not in park then no start but why? also i can't access the computers from the obd II port it has link failure. I watched a youtube video on how to bring up the dtc but thers nothing else there.

 

[Marde]

I am thinking if it thinks not in park then no start but why?

It's supposed to do that. If it starts while IN GEAR the car will jump out of the garage. -Ref the Farris Bueller movie. Try moving into Neutral, then attempt start.

also i can't access the computers from the obd II port it has link failure. I watched a youtube video on how to bring up the dtc but thers nothing else there.

Yep. Must Have OBD communication. If none, start there and find the fix.

 

[sailor]

TCM needs some precise alignment when changed out, there's a recent video in the MkII area on that.

It's in the MkIII problems area stickies, I'll post a link.

http://www.focusfanatics.com/forum/showthread.php?t=469009