Computer problem???

[Stites0518]

As some of you know we put our '96 Windstar in the garage to get a new transmission put in. (about 2 weeks ago). When the shop guys took it for a test drive the computer started commanding 2nd gear. It burnt up the gears and clutches in the new tranny and they had to rebuild it again. Then it started shooting codes about the ignition and also that the computer was commanding 2nd gear no matter if it was in park, neutral or some other gear. So my husband took out the after market alarm system. The previous owner had installed it. That took care of the ignition codes. But the computer is still commanding 2nd gear. A specialist is coming to the garage that it is STILL in to take a look at it tomorrow. I do medical transport with this vehicle and I'm losing major money. My husband checked the ohm's on a wire from the transmission to the computer. He said that the wire was showing the computer commanding 2nd gear. All the solenoids are in good shape. No codes from them. Would a quick fix be to just go ahead and get another computer?? We've found some on ebay for as cheap as $20. They're used but supposed to be in good shape. HELP PLEASE!!

[Stites]

Thanks for throwing this up, babe.

I'm about to go get the numbers off the PCM, and I'd like to know whether or not the PCM in the 1996 models was used in other years/vehicles. Anyone got expertise in this matter??? Is there any part numbers I need to avoid???

[Stites]

Aiight, here we go.

At the plugin we have:

ML2-351 KIN0(zero) EEC-V

F68F-12A650(zero)- AA *D2WVB0(zero)9RNY50(zero)*

G NPF 5H163

On the back of the PCM:

F68F-AA NPEF

KIN0(zero) 50(zero)8171

Could someone tell us what's what on here? I believe the F68F-12A650-AA is the part number for the PCM, and the KIN0 has something to do with the programming on it... am I close???

[wiswind]

The best place for that information would be from FORD.
I have not read any posts giving your problem..... so sorry that I can not be of more help.

[CoachKarl]

Oooh! . . . FAIL?!?
A brand new (ly rebuilt, or pulled from a wreck) transmission?!? FAIL?!? Why that NEVER happens. EVER! EVER! EVER! (I tell that to all my Southern Appalatian customers).

My advice is . . . .
1. Stick it to the installer. a. where did the "new" tranny come from?
2. You paid him to FIX! it.
a. Auto Zone would charge you XXX just for the rebuilt trans, and you (fixer) only charged me YYY!!!
3. Force the mechanic to level with you, then solve this problem.

Post back if I'm wrong.

Karl

[comanche64]

Stites: Two things if fluid is removed and the same amt isn:t put in:This car & some Chrysler cars will go into protect mode and car will not shift to High
Gear.#2 should power be removed from P>C.M (Brain) and this will happen when both negative and postive Battery cables are removed.Should Mechanic
jump in car and drive for a road test this will happen;Let car curb Idle ;make sure proper Amt of fluid after working thru all gear positions;Then drive car 10 miles or more so P.C.M.(Brain) can reset its Memory.
If you would like I can get this caution from my CD on this warning.I found this after replacing drive belt;I had removed power neg and Pos at battery.I have been 3 days trying to fix a problem I caused/Comanche

[Stites]

Well Comanche, the thing that gets me AND the trans man is that the PCM is ALWAYS requesting 2nd gear, whether it's in PRND or 1. In 2, it requests 3rd. I'm totally confused... not that it's hard to get me that way.

[comanche64]

Originally Posted by Stites

Well Comanche, the thing that gets me AND the trans man is that the PCM is ALWAYS requesting 2nd gear, whether it's in PRND or 1. In 2, it requests 3rd. I'm totally confused... not that it's hard to get me that way.

Stites:As I undestand it and ;I sure could use a whole lot more understanding
Some cars have this caution(Put back the same amt of Trans Fluid that was
removed}Else Transmission will set self protect Mode 2nd Gear.
I have another thought also/The person that road test car had to know He
was over reving Eng./If Transmission was not shifting up to 3rd/You can"t
get 65mph in second without bumping 3000 R>P.M /So why burn up Eng and
few other things I can think of.Comanche

[DRW1000]

Could it be something as simple as the linkage or signal from the gear selector switch being stuck in 2nd? Since it is electronically controlled (or so I think) the electroncs could think that 2nd is command all of the time.

[wiswind]

I have looked up some information.....
This is for 1996 3.8L

Transmission Range Sensor (TRS) has a series of dropping resistors, so the voltage to the PCM will vary with the gear selected.
The TRS input to the PCM is on Pin 64.

Solonids 1, 2, and 3 control the selection of gears 1 through 4.
The PCM connections are
Solenoid 1 Pin 27
Solenoid 2 Pin 1
Solenoid 3 Pin 53

The AX4S connections are
Solenoid 1 Pin 1
Solenoid 2 Pin 6
Solenoid 3 Pin 8

When the PCM is calling for 1st gear, SS1 is OFF, SS2 is ON, SS3 is OFF

When the PCM is calling for 2nd gear, SS1 is ON, SS2 is ON, SS3 is OFF

When the PCM is calling for 3rd gear, SS1 is OFF, SS2 is OFF, SS3 is ON

When the PCM is calling for 4th gear, SS1 is ON, SS2 is OFF, SS3 is ON

When the PCM is calling for P/R/or N, SS1 is OFF, SS2 is ON, SS3 is OFF

When the Gear select is in 3rd, as "engine brake" and PCM is calling for 3rd, SS1, is OFF, SS2 is OFF, SS3 is OFF.

When the vehicle is stationary, I would expect the PCM to call for 1st gear
REGARDLESS OF WHAT FORWARD GEAR YOU HAVE SELECTED.
This is because the vehicle starts out, from a stop in 1st gear and then shifts up to the gear selected as the vehicle speed increases.

This may account for the Shift solenoid #2 always being ON when the vehicle is stationary.

I have not actually troubleshot these signals, so I do not have first hand information from any experience.

Remember, not going above 2nd gear is "limp mode" meaning that the tranny is not happy with something.
As comanche64 stated above, that should NOT in itself damage the transmission as it will be obvious that the transmission is not shifting......as the engine speed increases.... So one would cruise along slowly back to the shop.
A transmission tech should be familiar with this condition.

I will also mention that there is a TSB that states that the transmission cooler needs to be checked and backflushed, to make sure that it has not become clogged by crud from the failing transmission. If you cannot clear the cooler by back flushing, it will have to be replaced (the whole radiator unit).
If there is not proper flow through the cooler, the new transmission will overheat and fail.

[DRW1000]

Originally Posted by wiswind

When the vehicle is stationary, I would expect the PCM to call for 1st gear
REGARDLESS OF WHAT FORWARD GEAR YOU HAVE SELECTED.
This is because the vehicle starts out, from a stop in 1st gear and then shifts up to the gear selected as the vehicle speed increases.

Are you certain of that Wiswind? Is that something only recently? For some reason I always thought that an automatic in "2" started off in 2nd and stayed in 2nd. This was a way to get going on ice and slippery surfaces. I don't know why I always believed that though I could be wrong.

[wiswind]

To be honest, I don't know.
I posted the solenoid values from a chart.
I guess the way to find out, would be to set the selector to 2nd and start out.....if you feel the transmission shift, then it started out in 1st.
If not, then it started out in 2nd.
Again, I am not experienced in this.....
Of course, the original poster cannot do this.
But....maybe that would be a reason for his getting a different condition when only when 2nd was selected..... I was trying to figure that out.

[Stites0518]

This is Stites on my wife's login... too lazy to change names, I guess.

Wiswind, you are the MAN!!! My wife says GOD BLESS YOU!!!

The TRS is working and adjusted properly, I believe. I ohm'd the switch out and went through the ranges and wound up with the following:

P - 735 ohms
R - 540 ohms
N - 386 ohms
D - 260 ohms
2 - 156 ohms
1 - 71 ohms

I'm gonna check continuity on those pins this weekend, as well as check the solenoid actuation in the specified ranges. Thanks for the info... how do you do it???

[wiswind]

I have not ohmed out the TRS, but your readings make sense, as P is at 1 end (closest to the PCM connection) and 1 is at the other end (farthest from the PCM connection. As you move the selector from 1st to P, you add more resistors to the lineup.

I got the information from AlldataDIY.
It has been a good investment.
Even if you are having the work done, it is good to be able to read up on what is being done, and they give the standard times and part costs, so you should know a ball park figure on what is involved.

[C. Cleve]

HI, You gys ar still at this thing? FORD shopmanual with flow chart's, Ford trans tester, Ford scanner, DON'T skip any steps in the flow chart sequence, See Ya, Clay..