My 1991 E 350 7.3 idi Van have shifting problems over years. Found no way to solve problems in Germany due unknowledge of US Ford Tranny technique. Try to find a way on FTE-Forum. My first post. Sorry my language.
The facts:
Two trannys damaged, replace TECA (EEC IV), replace FIPL (TPS) can´t measure FIPL, can´t read codes
The mystery:
Signal return line on FIPL give me in KOEO 5 Volts, TPS zero, and 5 Volts from TECA(normal).
Question 1: what function have signal return? Read “ground” in diffrt. Threads-but why not in description of TECA contact ( Ground on pin 20 and 60 remember?)
Question 2: where can 5 volt come from? A short in wire or fail TECA?
signal return ( grey/red wire on my model) is connected with MLP and BARO and VIP self test connector too and it´s resistance over 5 ohm.
Question 3: How to measure or find a short under this circumstance?
Question 4: may be the ECU is fail? Take under KOER the oil pressure sensor off - the gauge show right - signal arrived – ecu works fine - i´m right?
My idea: replace “signal return wire” (big job) than be able to get codes and to measure FIPL.
Have bought EEC IV (60 pin) break out box for 130 + tax +freight, to absolve measurement under real conditions in future, good idea?
That’s all just now, thank you for helpful response.

 

The signal return is a dedicated sensor ground wire. The signal return wire should be at 0 volts at all time. If the signal return wire is at 5 volts, the wire is open-circuit somewhere between the FIPL TPS and the EEC-IV.

 

Thanks Ian...was good information. try to find open circuit...

 

It may be worth trying to run a ground wire directly from the signal return wire at the FPL to body ground, or the EEC ground and seeing if the problem goes away.

 

Signal return isn't ground. Don't run that wire directly to ground.

 

Thank you Mark,
try this today ( with my "new" break out box ): get 5,03 Volts on contact 46 ( signal return) with all sensors connected. After disconnecting them all ( BARO, Trans, NPS and TPS) get 1,04 Volt...also on STI on VIP-Connector. Searching in WEB and found something about mailfunction on VIP Connector: if there is a measurement about 5 Volt on STI you can have a bad ground anywhere...why? Ican´t explain
Will clean them all now (grounds) and see what happens..

 

no solution until now. when searching a new EECIV-TCM i´ve found an eletronic-expert in croatia and contact him. Here our mails.( the last on top)



Hi Ivan,



thanks for your comment. that explains, why i get 5,.. Volts on signal return. And the function of signal return...check if sensor works . But that means that all comments in forum ( FTE..Ford Truck Enthusiasts News - Ford-Trucks.com.) are false. in every description to installing and callibrating TPS (throttle position sensor) they rote...signal return must be 0 (zero) volt.

why should a sensor have 3 contacts instead..? i was confused all the time and measure, measure, measure...

I´ll place your description in that forum to discuss and inform you about result.



Wilfried Ristow
Goethestr. 8
59439 Holzwickede
Tel. 02301-13203
mobil: 0151-67501331


-----Original-Nachricht-----
Betreff: Re: Klemme 46
Datum: 2016-03-16T13:57:32+0100
Von: "BIZTeam Automotiv" <bizteamautomotiv@gmail.com>
An: "Wilfried Ristow" <w.ristow@t-online.de>
Hi

I have checked, this ECU on line 46 have signal return, it means this line is reading voltage from sensors, Controling which sensor to read is regulated by multiplexed switching beetwen them.

ECU first open VREF pin, then send power supply to 1 sensor and it reads value from it, he knows what he is reading because he is supplying 1 by 1... and reading SIGNAL RETURN 1 by 1...

You have 4 sensors or return line, MAF, FEUL LEVE in Pump, Temp sensor in gearbox, and shift sensor.

1 of them could make trouble if signal line is grounded... or SIGNAL return klemme inside ECU is defect.

This is typical Voltage measuring technique.

2016-03-14 17:33 GMT+01:00 <w.ristow@t-online.de>:

‎Mistake of my. Not 57 ( 12 Volt) offcourse.
failure on 46 ( signal ground) should measure 0 Volt but get 5,5 volt.


Gesendet von meinem BlackBerry 10-Smartphone.
<table style="background-color:white;border-spacing:0px" width="100%"> <tbody><tr><td colspan="2" style="font-size:initial;text-align:initial;background-color:rgb(255,255,255)"> Von: BIZTeam Automotiv
Gesendet: Montag, 14. März 2016 14:41
An: w.ristow@t-online.de

Betreff: Re:

</td></tr></tbody></table>
Hi

Klemme 57 is power supply for shift selenoids and for ECU supply.

You must check x joing of those connection, you have missing 12v from that relay. On igntion on klemme 57 you need to have 12Volts.

Regards

2016-03-14 14:10 GMT+01:00 Wilfried Ristow <w.ristow@t-online.de>:

Hallo Ivan,


just call´d you for my ECU. some informative files attached (also Bus images to get imagine what i work for), wish you can read them.
i´ll try again to fix the problem without new ECU (TCM=TECA = EEC IV). May be there is a connection failure on EEC IV Relay...

best regards


Wilfried Ristow
Goethestr. 8
59439 Holzwickede
Tel. 02301-13203
mobil: 0151-67501331




what is true for signal return measure??

 

The TP Sensor gives various voltages between 0 and 5 volts depending on how much the gas pedel is depressed.

 

https://www.ford-trucks.com/forums/1...ions-only.html

 

installed the "Baumann" shifter after all and it´s running fine now

 

That's one way to do it.