Fiat Multipla JTD 115, bastard running problem.

[Lankytim]

Hi all,

 

As mentioned in the GOM thread, the Multipla has developed a problem which I suspect is my fault.

 

I swapped the fuel filter last week and everything seemed to be running fine but I then remembered that i'd forgotten to plug the moisture sensor back in. As soon as I did that it went into limp mode and I got "Engine control fault, see garage LOL" on the dash display along with the EML. On inspection the wiring to the moisture sensor is damaged, so that may have been the problem there. On top of that the speedo stopped working!

 

Anyway, even after leaving the battery unplugged overnight to reset the EML  and disconnecting the moisture sensor the problem persists. I have gone on a few test drives and on the last one the speedo jumped back into life, but registers 35-45mph, even when the car is stationary. Weirder still the mileage clocks up and the handbrake alarm goes off too, the Multipla obviously thinks its doing 40mph on an A road when it's sat on the drive at home!

 

Maybe the fuel filter is a bit of a red herring and the speedo sensor is faulty, or I somehow damaged some wiring when I was swapping the filter. Either way, I'm stumped.

 

HELP!

[Lankytim]

Just been underneath (in the bastarding bastard rain) and unplugged the speedo sensor, with it unplugged the speedo stays on 0, with it plugged in it bounces around 40MPH. Can I take it that its faulty?

[scooters]

Yes, I would replace the Speedo. I would also change the filter again. Did you bleed the filter after installing?

 

Sent from my HTC One X using Tapatalk

[Lankytim]

Yeah, I've stuck a fresh filter on and there's no difference. the system is self bleeding so no problem there. A mate of a mate is hopefully going to stick it on his diagnostics machine this week and find it what's wrong with it.

[twosmoke300]

Is the fuel filter right above the speed sensor on the gearbox?

water/ diesel may have filled the connector up when you changed the filter

[Lankytim]

I thought that but it's not, the gearbox is at the other end with the sensor buried at the back.

[Lankytim]

The sensor is this part,

 

46817375 SENDING UNIT

 

Google is turning up blank with anything in this country. GSF and ECP are no good either. grrr.

[Lankytim]

Hi all,

I had the Multipla scanned today, here are the fault codes...


The following could be reset and didn't come back,
P1555
U1600
P0500
P0180

These are on full time and can't be reset,
P1612
P0236
P0404
P0638
PO645
P0101

The fella told me that the battery is only knocking out 6v and the clutch pedal switch seems to be sticking. He thought that many of the problems could be due to the diesel filter sensor not being connected up (the wiring is damaged) and the MAF meter being on the blink. Oh, and the speedo sensor is kaput!

He didn't charge me, I think he felt sorry for me!

[saucedoctor]

FWIW, my mate's Range Rover did screwy things when the battery was duff. A new batt sorted all the weird codes out.

 

You probably know:

 

P0236 is map sensor or Turbo boost pressure sensor

P0404 is EGR

P0638 is throttle actuator

P0645 is the aircon compressor clutch relay

P0101 is MAF

[Lankytim]

Thanks for that,

 

The EGR has been blanked off, so that explains that particular ERR0R

The aircon doesn't work, maybe a new relay will fix it?

P1612 refers to the fuel filter sensor, which is apparently a heater and water detector sensor. Mine isn't connected as the wiring is all borked and shorted out. I didn't think I needed it. RONG.

 

 

I have a spare battery, so i'll stick that on and see what happens. It starts in the morning fine so not sure where the 6V comes from.

[Richard]

If it starts but only 6V is finding its way to the diagonostic socket that suggests either a bad earth or bad connection somewhere.

[Lankytim]

Right, time for an update...

 

I haven't thrown it into a hydraulic crushing machine, After diligent googling and a suggestion on the Fiat forum I checked a 15A fuse in a "secret" location under the dash on the passenger side. It was blown, apparently the sensor for the fuel filter is on the same circuit as the speedo sensor and the turbo actuator relay. The wiring to the fuel filter sensor was damaged and had shorted out, blowing the fuse and monging the speedo and disabling the turbo actuator relay, putting it into limp mode. I've fixed the wiring to the fuel filter sensor, replaced the fuse and VOILÀ, The limp mode has gone but I still have the EML light and an annoying beep and warning on start up. I'm pretty sure the MAF sensor is fecked so i;m ordering one of those, then i'm going to get the codes reset and see what happens.. Fingers crossed....