P0700 for transmission control

Hi,

I used my wife's van yesterday and it was fine. This morning, it's broken. Obviously, I'm suspect since I was the last to use it. Lol but I've been trying to get some info and thought you guys could help. Here are the specs

Here's what's happening - Wife went to drive it this morning. It was 'bucking' during downshifting only into 2nd and 1st gear. No issues accellerating. She brought it back, and it was low on fluid. I topped it off. Fluid didn't appear burned or red/brown. Still Bright. I drove it around, and felt the bucking. While driving it all the sudden lost all gears but 2nd (limp mode) but after shutting it off, I had the gears all back (out of limp mode) but it was bucking downshifting into 2nd and 1st gear again. Then it went back into limp mode.

Here's what I've done - Pretty much nothing. It's sunday. But. I thought maybe it was bucking because it was low on fluid, and the P0700 code needed to be cleared out. I disconnected the battery for about 30 min, reconnected it, and without even starting it, and just turning the key fwd/back 3 times, the P0700 is there. Didn't even start it.

My question is shouldn't the vehicle need to be driven? I thought that the sensors in the Transmission sent info (above or below spec) to the TCM and it interpreted it and sent to the PCM to put the CIL on or off. Or some variation of that. Would the 0700 being there after clearing codes indicate that the TCM is so broken, it's picking it up immediately, without driving it?

I'm a novice, and don't pretend to do the good work you guys do, this is just a product of knowing a LITTLE about cars (hey, I own a 91 Bronco - you tend to learn a little owning that hog) and I've been googling all day.

Any help would be more than appreciated

Does that need to be taken to a Dealership or Transmission center to do? I'm assuming they would charge for that?

Also, would one of those things cause it normally to give just 1 error code (0700)?

Sorry for the delay in getting back here. Had some personal issues come up and the van had to sit for a while. I did get it up to one of the local transmission shops yesterday.

He said he wasn't getting any codes from the TCM, so he cleared the P700 code, drove it around for 10-15 min and it was fine. He said he felt a slight 'flair' going from 3rd - 4th. He drove it around more and then the vehcile went into limp/safe mode again. He sait it gave a P700 code, and now the TCM is telling him "4th Gear Ratio Error" He said he checked the CVI (Clutch Value Index) data, and it all looked within spec. He said to further diagnose it, he'd need to remove the transmission, crack it open and go through it.

He said he can give me a price once he finds the internal issue. He also said that if he finds the problem, and I don't like the price, he'll put the transmission back together, and in the vehicle for $389.

My question - With ONLY a P700, and nothing else showing, could the issue possibly be an input/output sensor, or would that have shown up in the Van's computer. Is it possible that just having a P700 is not internal? I originally researched and saw the TCM's DO go bad, but he's saying it's fine because he's not getting some BIOS error when reading the codes.

Is there any additional testing I could do? Is there a way to pull the input/output sensors and check with a multimeter, or maybe some of the other sensors that could possibly cause this?

He didn't give me any codes (not sure if that was purposely or not). All he told me is that it gave him a "4th gear ratio error"

Kinda baffled at the need to drop a transmission and crack it based on him telling me it drove fine for 15-20 min after he cleared the codes till it threw the 0700 code again, and that everything else seemed to be 'in spec'

Would a sensor necessarily give a PCode? I think I read that there was a PCode associated with a bad input/output sensor. But the odometer never gave anything other than P0700 (and I think an O2 sensor that just went bad)

Let me ask you a quesiton about this. Prior to taking it up to them, I had removed the battery cables, and let it sit to clear the code from the car.

Prior to even starting the vehicle, the P0700 had come back.

Would you think the TCM is the likely culprit in that situation?

Previously you mentioned P0700 was informational, but what you posted seems to imply that if you clear the codes, and P0700 comes back (even if it's the only code) then it's a faulty TCM unless I read that wrong.

Is removing the battery cable sufficient enough to clear the P0700 and if so, if it came back without even starting the car, is that normal? I would have thought it would have had to be driven. I've got no way to verify what he claimed (as far as clearing it and then it coming back 15-20 min of driving later). In my driveway, I removed the battery cables, reconnected and it came back.

He did say initially there were no codes in the TCM so he cleared it, and when P0700 came back THEN he saw this "4th gear" code.

Could he be blowing smoke up my TCM maybe?

EDIT - The more I think about it, maybe the P0700 did come back when I started it, but it DEFINITELY came back without me shifting the shift lever or driving it.

Just to clarify. When you say this, you mean the PCM? I have no way to check the codes in the TCM, only PCM. The first time the guy from the Transmission shop hooked up the computer to the TCM, he told me (when I dropped it off) that there were no codes in the TCM but he'd go through the electrical system. It was in limp mode and driven about 20 minutes to his shop in 2nd gear from when I cleared the codes last.

After he 'cleared the codes' he told me that the PCM 0700 code came back (with 20 minutes of driving), and he checked the TCM code and got the 4th Gear Ratio Error code.

If I get her back from him (Probably Monday) and Unplug the battery for 20 min or so, hook the battery back up, I should check codes (KOEO), then start car (without moving gear shifter) and if the CIL comes on, and the PCM is giving me P0700 without engaging transmission or driving, then it would indicate a bad TCM?

I guess what I'm wondering here is if I clear the codes (disconnecting battery) and start the van and instantly codes come back without moving, is that normal? Shouldn't the car have to be driven, for something to be out of spec or out of range for the TCM to find out and tell the PCM to give a P0700? I was thinking that for the Van to give a P0700 (PCM code) it really would need the TCM to see something was wrong. Can a TCM see something wrong without it even being driven or engaged?

I'm leaning towards the TCM being bad based on the cleared codes coming back the moment the vehicle is started. Is that safe thinking?

I REALLY appreciate all the help. I feel like I'm close to getting this nailed down, I just want to make sure before I drop $200 on a TCM, that my thinking is sound based on how it's supposed to work under normal conditions.

As far as not trusting the guy, I used to be in sales. Very deeply. I just feel like he's pitching, price shielding me, and doing various other sales techniques, and I just want my car fixed, not sold on something.

When he first hooked the computer up, he was pushing buttons and at one point flashed past a screen that I saw the word "CRANK" on it. The screen after that told him the car wasn't in limp mode and he kinda waved it in my face to say "it's not in limp mode, you're actually STUCK in 2nd gear -oooo bad. When I questioned him on the screen I saw very briefly, he went back, cranked the key forward, redid his test, and all of the sudden it was in limp mode on his computer. His credibility kinda went down hill for me there. Also considering the P0700 came back INSTANTLY without driving it in my driveway, where he states he had to drive it for 20 minutes to get it to come back. Just feeling sour about him is all.

Thanks for the clarification.

I have read things that say you CAN clear the codes in a TCM by disconnecting a battery on this make/model and some that say you cannot, and a scan tool must be used to clear the codes. So I wasn't really 100% sure.

My thought was that if you CAN clear both PCM/TCM codes and P0700 is coming back upon starting the vehicle. TCM needs to be replaced

If you cannot clear TCM codes by disconnecting battery, then it's simply coming back on start up because TCM has the original error data and was telling P0700 time to wake up :)

I understand you to say say that the battery will clear PCM (P0700) and the TCM (4th Gear Ratio).

I'm going to see about getting it to another shop next week. I'm not going to say a word about another shop looking at it, and see where it goes from there. I'll ask the first shop for a print out of the codes and see what he says.

I'm just at a loss now as to why 1 time there were no codes in TCM, then when I left, he found em. Maybe I know the answer already thought.

Give me a few days and I'll post what happens next :) THANKS AGAIN!

Post subject: So What was the fix? Thanks

I ended up removing the connector which I should have done early, cleaned the connection which had rust all fixed!

I fixed my error code in 1 hour it's very simple all I did was call a junkyard to buy a transmission control module tmc just jack up the van on the driver side front wheel to change the tmc it's very easy the module costs was 75.00 bucks my check engine light went off without any problem you can reset it by turning the key on and off till the computer resets drive Van problem is solved my error code was 0605/0700

'97 T&C giving me a P0700 code. Reported loss of drive while driving. It came back after it sat. Any ideas, control moduale or something?