97 5.0L PCM - Ford Updates?

[410Fortune]

OKay here we go again....hahaha though all my problems would go away with the new 5.0L drivetrain, but NOOOOOOOOOOOOOOOOOOOO there are still some bugs.

I have been getting transmission sensor codes and also 02 sensor codes lately. The most common code I get is P0705, and P0135

705= digital transmission range sensor
135 = heated os sensor circuit failure, bank 1 sensor 1

After speaking with Baumman engineering (4r70W masters) I believe the 705 code is coming from the DTRS, when the computer sees a signal that is sent between P and R, their TCS controller ignores this signal because it means nothing. Ford issued a TSB for my 97 PCM to solve this issue. This leads me to believe my donor PCM has never had the updates performed.

The 135 code makes no sense at all because the sensor is new, wiring checks out, and I get the same code even if I install a new sensor.

recently the truck has lost OD intermittantly on the highway, now the OD OFF light is flashing.

I cannot pull any OD codes from the PCM.

My question is, anybody had similar issues with a 97-00 Explorer 5.0L?
All my research is pointing me towards having my PCM re-flashed at Ford, I hate stealerships, but of course I want this fixed. Cruising along at 75-80 MPH and the truck going into 3 from OD = no good...can you say red line?

Just looking for input from people who have experienced similar conditions.
Also I am aware of the updated shift solenoid mods for the 4R70W, this would be next after I eliminate possible PCM re-flash issues.

Any input is appriciated, thanks!

 

[410Fortune]

bump

 

[Cali' Explorer]

Random question, are you running an aftermarket chip at all? I haven't looked through your posts, but I had a similar problem in a 2002 Ranger Edge after installing a Superchip. Something was wrong with the program, and it would try to drop to 2nd whenever you floored it.... first time I found out was trying to pass someone on the freeway.... Sufficed to say the tach pegged well beyond redline (chip also removed the redline limiter, fun).

Other than that I can't say as I believe my computer has been reprogrammed.

 

[410Fortune]

Stock PCM. Thanks for the info!
Later down the road I will be looking into a OBD-II programmer, no chip in the PCM..

 

[Cali' Explorer]

No problem, I do also know that there were other issues resolved by flashing the PCM. I have heard that the flash also retards the timing some (to eliminate pinging/ticking). So that's another thing to keep in mind with this.

One other question though, have you gone through with contact cleaner on all the transmission related switches/sensors/plugs and cleaned the contacts up and put Dielectric on them? I'm sure you have, but I know in that past that has solved some intermittent and "Weird" electronics gremlins for me with my GF's VW.

Good luck, and keep us posted with how things go.

 

[clarkede]

I have a 98 XLT 5.0 that is having shifting problems (4R70W transmission). I thought it was the transmission, but after living with resetting the codes for a year, it is finally not shifting properly and so I had to take it in to the shop. The tranmission shop looked at it and said that they felt it was some sort of an electrical problem and not the transmission. The refered me to an automotive electrical shop who looked at it and tested the wiring and found no problems. The feel that it is the PCM that is causing the problems. Does anyone have any idea if this could be true. The codes that I am getting are:
P1746
P1747
P0741
P0743
P0750
P0755
Originally when I started having problems the Check Engine light would come on and the OD light would flash on/off. The transmission would shift a little funny, but no major problems. If I used my "code reader", I could reset the codes and the transmission would act like there was nothing wrong. Then after a few hours to a few days the code would re-appear and the OD light would flash and the transmission would start shifting funny. So I would just reset the code and everything would be fine. This cycle lasted for nearly a year.

Then a couple weeks ago I was on the highway and it did some bucking as it tried to shift back-and-forth into gear. The problem didn't last, but it was weird.

Then a couple days ago the transmission wouldn't go into 3rd gear. I had to down-shift the selector from Drive to 2nd. The engine would of course rev higher, but I was able get where I needed to go.

Today I changed the fluid, which was a little discolored but very clean. It didn't smell burnt at all. Very little grey residue in the transmission pan. I have 120K on it now and had changed the fluid at about 60K the last time. I know I should have changed it sooner, but it has been good and still looks great.

Does anyone have any suggestions?

 

[Glacier991]

Are these rebuilt 4R70W's? I am just coming up to speed on them, but I do there were DTR issues. Candidly I suspect my knowledge base is, at curernt, a little behind these issues though. 410, if the problem becomes more frequent let's discuss using the trans tester for yoou?

 

[Brian_B]

I want to follow this thread for possible future interest. I was thinking of someday putting an AOD into an older vehicle (if I can ever find the one I want). If bauman can control a 4R70W, this might be a better way to go.

 

[Glacier991]

Take this advice with a grain of salt... but I think the guts of the 4R70W can be retrofitted into the AOD case. The AOD can be built as strong as any tranmission out there. I am learning daily more and more about this family....the main difference is the EPC in the 4R70W..... hence the HUGE OD servo in the AOD and the relatively small one in the 4R70...because we can increase pressures.

Anyway.... keep that in mind.

 

[Brian_B]

Hmmm...good to at least think about. I am currently looking for a decent 56 f-100, but so far no luck in a price that I can afford.

 

[exploded99]

CLARKEDE remembered seeing this awhile back - may be worth investigating. A lot of your codes match this - it was issued for 99's, but when the shoe fits....

SORRY to 410Fortune for putting this in his thread, you may want to start your own if you need more help.

FORD:
1999 CROWN VICTORIA, MUSTANG, ECONOLINE, EXPEDITION, EXPLORER, F-150, F-250 LD

LINCOLN:
1999 TOWN CAR

MERCURY:
1999 GRAND MARQUIS, MOUNTAINEER

This TSB article is being republished in its entirety to include additional vehicles and to correct the Service Procedure.

ISSUE
Intermittent Transmission Control Indicator Lamp (TCIL) or Malfunction Indicator Lamp (MIL) illumination may occur on some vehicles. The following Diagnostic Trouble Codes (DTCs) may be stored in memory: P0741, P0750, P0755, and P1746. This may be caused by the solenoid interconnect molded lead frame not being fully seated or the bulkhead interconnect clips not being fully seated between the solenoid interconnect molded lead frame and bulkhead interconnect.

ACTION
Verify the solenoid interconnect molded lead frame (-7G276-) is fully seated. If no concern is found, then inspect the bulkhead interconnect terminals for spread and/or not fully recessed. Refer to the following Service Procedure for details.

SERVICE PROCEDURE

1. Perform normal diagnosis for DTCs retrieved as outlined in the appropriate 1999 Workshop Manual. If root cause is not determined, continue with this TSB.

2. Remove the transmission oil pan per the appropriate model Workshop Manual, Section 307-01.

3. Verify that the solenoid interconnect molded lead frame is fully seated on all the solenoid connectors (Figure 1). If the solenoid interconnect molded lead frame is fully seated, then gently remove the solenoid interconnect molded lead frame, valve body, and bulkhead interconnect (-7G276-) per the appropriate model Workshop Manual, Section 307-01.

4. With the bulkhead interconnect removed, push down on the terminal cover and check to see if any of the terminals are slightly protruding above the plastic cover (Figure 2). Gently pry off the terminal cover using a small screwdriver (Figure 3). With the terminal cover off, inspect the bulkhead interconnect for spreading terminals (Figure 4). If the bulkhead interconnect terminals are spread or slightly protruding above the plastic cover, replace with a new Bulkhead Interconnect (F8AZ-7G276-AA).

5. Reassemble.

(DIAGRAMS DELETED in this post)

 

[Glacier991]

That is assuming you have the hard frame harness and not the soft wire.

 

[410Fortune]

Allright here we are again.

A year later (since the conversion) and I just pulled these codes from my BII this AM.
I cleaned the MAS yesterday and pulled the EEC fuse, on a 10 mile trip the CEL did not come back on. then this AM when I got in and started her up the CEL was on.

Pulled these codes:

P0135
P0705

135 = bank 1 sensor 1 heater circuit malfunction.

Very odd since the heater circuit is two wires for 4 sensors, I will be pulling my floor shifter tonight and tripple checking the wiring between the PCM and the plug for this sensor.

P0705 = transmission range sensor circuit malfunction

Again I will check the wiring, the 02 sensor and trans wiring do go through the same plug on the trans so I am going to take a close look at that sucker and again check the continuity between the DTRS and the PCM


Other then that I am at a loss, short of swapping out my 97.5 5.0L PCM for another...

Will my scantool be of any use for diagnosing these codes?
I have the scantool and laptop software but my OBD2 diganostics port in the BII is missing 1 power wire before I can use it....so it may be worth the trouble of finally hooking up this power wire if the software can shed any light on these codes?

I would really hate to take my PCM to Ford......

 

[97BlackX5.0]

i had my 4r70w OD light blinking and shifting funny similiar to what you had. turned out that I used mercon instead of mercon V. When it was really cold it didnt like the difference or something. Never had the downshifting problem although a common problem with the 4r70w is that the check ball in the direct clutch drum can get a little piece of gunk in it causing the clutch to not unlock or lock fully and burning up the direct clutch pack. In my case I lost anything after 3rd gear it would neutral out. To temporarily solve the mercon problem there is some stuff you can get called lubeguard.... lots of transmission shops put it in freshly rebuilt trannies. This cleared up my blinking overdrive light and the weird shifts until i got to change the fluiid. The clutch pack required pretty much a entire teardown in which i also updated the accumulators and did a few other updates. I personally would do a fluid change with a shift kit and see if that helps and do the accumulator updates while you have the valve body out. There are also a few issues with the EPC in the valve body having an updated part as well as the range controller.... Hope this helps. I rebuilt mine to get to the burnt clutch pack around 106k miles and other than seals and new friction components did not require any other parts.

 

[410Fortune]

say what now? I have no shifting issues, jsut the 135 code which is DTRS circuit failure.

the OD light is not on, the 4r70w shifts flawlessly.
I have Mercon III in there with a bottle of lube guard, my 97 trans asked for mercon III not V

I believe it is either my wiring or the PCM, I will be checking the wiring ASAP (again)

The beginning of this thread was just after the conversion was complete, I was having some issues back then but have solved them. My trans issues were due to the pass side wiring plug (for the shift solenoids) was not seated fully.

P0135 is the only trans related code I am getting and since I am also getting a bank 1 sensor 1 heater circuit malf code P0705 I will be tearing out my floor shifter to gain access and triipple checking my wiring, it would be pretty funny if I jsut had these two wires crossed, also quite possible even though I did not really touch the trans harness when I did the conversion......

 

[97BlackX5.0]

oh i guess i skipped a few posts. I believe when i was doing some research that there were two range sensors too.. a gray one and a black one.... sorry for the confusion... i thought you were having problems shifting as well

 

[410Fortune]

the story on the DTRS apparently is 96-97.5 is analog and the 98+ is actually a digital signal, so you can run into problems putting a later model trans in an earlier truck or vise versa if you dont know this...I am guessing the digital one is grey then though I have never seen one (yet)

My DTRS came with the trans, wiring and pcm all from one truck so this was never an issue...my shifting problems were from the plug not being seated fully, only took me two weeks to figure that one out! hahaha

Thanks for the input though I am sure it will help somebody.

What I am looking for feedback on is this:
I heard a rumor (at this point) that the 97 PCM's had issues with throwing flase 02 sensor and DTRS sensor codes, I was told Ford issued a recal for this, requireing the PCM to be re-flashed (or as most dealers do, sell you a new refurbuished PCM for $350+)

I would like to know if this is a rumor or true, if anyone had these issues with their PCM. As I believe my wiring is 100% correct and the codes are false..

 

[clarkede]

Just a quick follow up on the original post. I took the car to a transmission specialist, and they hooked up the electrical harness and did a harness wiring test which showed no problems (and it only cost about $10 to do - which I was shocked that it was so cheap). I then took the car to the dealer and they recommended replacing the transmission (for about $3000). I told them that I wanted them to open up the transmission and look for loose wiring due to a post I had seen on a Technical Bulletin that listed a wiring problem. Sure enough, that is what the problem was. It cost about $500 which included a transmission fluid flush.