Hi, greetings from Holland

My parents bought a Hymer 574 Fiat Ducato with an automatic transmission. They want to travel, but the transmission gives problems.

The red warning light can go on after using the shift selector at any time, and the gearbox then only operates in protected mode (3th and reverse gear only).
After one or two restarts (waiting a few seconds) it works again normally. It happens with cold start or with hot engine. Not a comfortable idea driving through the mountains.

Three different specialist companies looked at it. So far they did replace the PRND switch on the gearbox side - confirmed the magnetic switch on the pedal.
The ZF importer in Holland suggests it is a Fiat specific problem. They concluded the gearbox itself is OK and send my parents to Fiat.
Now the Fiat dealer is waiting for tips from Italy... They could make a readout while the problem occurred but don't have an idea how to solve it.
Just replacing the PRND gear selector switch would be expensive (1.300 euro - parts only) and might not solve the problem.

It is a Hymer 574 / Fiat Ducato
build september 2003
ZF 4HP20 (KW2) transmission

read out computer during the problem:
P0705 Gwear lever selector (posit.P,R,N,D) Intermittent Signal (not valid)


Any suggestions are very welcome


Groeten,



Viv

Hi Viv, welcome to the FF,

Possibly a faulty transmission fluid temperature sensor or the wiring from it to the ECU forcing the transmission ECU into protected mode.

Dave.

You are fast to react Dave! Thank you.

I hope it is the sensor... the wiring is all so difficult to get to. The dealer did test the wiring, but I guess it is not a guarantee ...
Your tip will be the highest on our list.

... the strange thing is that in the manual it states that the indicator should blink and the gearbox goes in 'safe mode' - but this indicator light stays on and evokes 'safe mode'.

Seems you're not the only one to have this problem, there's another post on it here:

https://www.fiatforum.com/ducato/143757-gearbox-problem.html

Unfortunately there's no response to that post but it may be worth doing a google search to see if anyone else knows anything about it.

I also seem to remember seeing a Dutch camper van site somewhere but can't remember the name of it. I'll post it if I can find it.

Dave.

The last post on this thread may have found a cure:

http://www.motorhomefacts.com/ftopic-20313.html

Dave.

WOW!!!

i did do some searching on the FF but didn't find it

Thank you!!!