Torque converter won't unlock at times
 

Hi Guys,

Okay, I've been scratchin my head and checking everything I can think of that would be causing this, but no luck.....

'99 Dodge CTD, 47re tranny

When driving in OD on the freeway, OR when driving around town with the torque converter locked up, at times the TC will not disengage when I let off the throttle, or hit the brakes. It will only disengage when I hit the "OD off button" or when the truck slows to around 25-30mph. Make sense?
I serviced the tranny about a month ago, new filter and ATF 4.
Batteries are about a year old (Optima red tops), cables are clean and tight (and new).
Any ideas what might be going on?

On a side note, I used a couple quarts from a gallon jug of ATF that had been open for awhile.....Not sure if ATF can go bad, or cause problems like I've been having??????

theres a diode that goes in the pcm to prevent the tc from staying locked , maybe someone will know more about it

Thanks DieselMinded.
When you say "diode that goes in the PCM" do you mean "goes" as in it breaks, goes south, etc.?
I've been thinking it could be the PCM, but I haven't heard of those being a problem. I've got the DTT noise filter on the PCM and all connections look good there too. I'd hate to replace the PCM, they aren't cheap.

No you splice a wire in the PCM and add the Diode

Call Severaces and ask for Brian 1-740-743-2100 tell him what your trannys doing and ask him about the PCM Diode

If Brians not available Roger will help you

I had the same problem. It was fixed by grounding the PCM and ECM to the battery negative terminal.

Once I got a solid ground on both, it cleared it right up. Not sure the 2nd gens, but I have an 03 and it was the last year they used that technology. Mine is located in the engine compartment on the passenger side firewall.

I hope yours is an easy fix.

Good info, thanks guys!
I'll start with the extra ground to see if that helps since it's the easiest and quickest thing to do.

Any updates??

This is a good one......
Turns out the wire loom that holds the APPS wire (and a few others) was sitting on top of the alternator. I zip tied it up out of the way and the problem disappeared.
These trucks are VERY sensitive to electrical noise and this was another case of it. Thanksfully it was easily solved.:U:
When I first bought this truck I had a bunch of similar issues with the trans, bad grounds, bad batteries, etc. so I learned a lot from that.
Thanks for the help guys!

Good to hear you got it solved. :U:

Good deal!! :U: