Technical The saga coninues...

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Technical The saga coninues...

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After getting the earth strap 'sorted' the car is continuing to throw up a power steering fault code and is now sounding like a bag of spanners. My daughter tried to drive it over to mine today but she described the steering as being clunky and spinning..nothing like she was used to previously.
Any positive suggestions as where to start?..
I have suggested she contact the garage whio 'fixed' the faults originally.
 
I picked the car up today...first few minutes of the journey were shall we say...interesting.
Wheels seemed to be spinning,power steering was intermitent and then absolutly no power steering at all.
Id forgotten how heavy the steering is without power steering.

I have just disconnected the battery and wil check over the other earth points as in the FAQ.

My cheap scanner showed no fault codes so I'll take it to my local garage and use thier snap on kit and see what shows up.

Any ideas?..pointers?..
 
Hi (who BTW?),

I'd have a look a the wiring from the battery to the Electric Power Steering unit.
There is a dedicate 70A (huge) fuse on the battery itself OR in the distribution box (depending of building year I guess), check for corrosion / melted connector.

On the PSE You'll find three connectors: Mains for both positive and negative power, CAN communication and analog signals in and out.
Check them for loose connection / corrosion (not likely) and measure 14VDC(ish) is present on the mains when engine is running. Grounding point (C014) needs to be ok of course ...

An important signal is the D+ that tell the controller the engine is started (or not), it needs checking too, that's pin #3 on connector C.
IMPORTANT: Fiat PROHIBITS measuring signal with "standard" meters for signals coming from the built-in torsion sensor since doing so may destroy it !!

I have attached a few Drawings that might help you a bit …

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
 

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  • Electric Power Steering motor driver.JPG
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My name is Nik..
This morning I re-connected the battery..no change.
I then removed and cleaned up the two earthing points under the ABS unit,after diconnecting the battery again.
Couldnt find the third on the drivers side leg at all.
Copperslipped the earth points.
The gearbox one is new so left alone.
No change.
No big 70 amp fuse by the battery or in the fusebox next to it. Biggest was a 60 amp and that looks ok.

Will try and find any other fuseboxes etc.

Thanks for the input Bernie ,was its the PSE?...
 
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Hi Nik,

Ooops, I meant EPS, Electric Power Supply … I you haven't that old fashioned fuse holder on the battery connector itself, then it's located in the distribution box, probably the large 60A, eventhough the EPS motor is said to draw as much as 80 amps in eLearn !!
Very first thing is to be sure you got all requested power(s) coming to the controler…

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
 
Hi Bernie,
I pulled the 60 amp fuse and the car was dead. I was thinking it may be the EPS fuse.
Do you know which one is ?...
When the cars turned on you can move to steering wheel freely,but this is accompanied by a chattering kinda noise. And more movement of the steering wheel than is reflected by tyre/wheel movement.
I will have to dig out my multimeter..my 'garage' is in two bedrooms and a shed whilst my new garage is being built..
 
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Hi Nik,

the 60A fuse sounds to be F2 in the drawing, which feeds the body computer (M001) with all the power it needs so it's normal the whole car died .

Do you mean the steering wheel just rotates a few degrees without action to the wheels and those would move only after that angle ? If so I'm afraid the torsion sensor (bad) or link to it (maybe a bit better) is the problem. No chance to tell without dismantling and this is not really recommended by Fiat as they claim it can't be rebuild with "factory accuracy".

So if you're pretty sure it's not an electrical issue (all powers OK) AND there is no other mechanical fault (have you tryed lifting the front wheels and check for free movement ?) it might be time to remove the EPS and inspect, either yourself or have it done by a specialist…

BRs, Bernie
 
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Can anyone point me to the location of the fuse for the Eps?..The steering wheel moves around very easily almost like the wheels arent on the ground. It makes no difference when the city button is on either..
 
Hi Nik,

so the EPS works then ? I'm confused now ! Or is it just intermittent ??
You say it feels very light as if the wheels weren't on the ground and the city switch doesn't make any difference; how about the city light on the dash, does it lit Always aswell ?? If so the City mode activation buton (I090) may be at fault, or it's signal wire shirted to ground. You really have to inspect the EPS loom …

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)
 
Sorry..I'll try and be clear. When the engines first started the steering wheel has very little resistance when turning. Its not smooth though and you can hear a slight 'grrrrr' type noise.Also when you turn the wheel to either side and let it go it tries to move ,kinda judders and does not remain in the position it was initially left in.
After a few minutes,less than a mile, the steering goes very heavy and its obvious theres no power steering.
The city button does light up but theres no noticable difference.
I was hoping there was a fuse or relay that I could check.
Its a massive coincidence that this only happened when the non starting/earth issue happened.
I will look into the wiring etc when its not cold and raining like it is in Derby atm..
The car's not needed so theres no rush to sort.
But would like to sort ..
 
Having exactly the same issue as you describe a while back I would really check the power connector and signal connectors going into the EPS located around knee height under the steering wheel. After driving through severe depression in the road at speed I had this happen briefly but got worse over a couple of weeks. When starting the car the steering was so light I initially thought a ball joint or rack link had broken. This was followed by first failing to assist turning to one side then steering itself to the other..Cleaning the contacts carefully sorted all the issues. Hope you get lucky with a simple fix
 
Had the codes read today..C1002,cam phase solenoids...is this a complete replacement or can any parts be replaced?
I have stripped the plastics off the steering colum but not too clear on which to clean..
 
No need to remove any covers..the connectors are visible above the pedals. Just need to be a contortionist..
 

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WTF!!..I'm 6'2",14 stone and 56..started to panic when I was upside down on the drivers seat with my stomach stuck on the steering wheel.I got one off but not the other two,some kinda clips..will try again but what!!!..
 
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