Technical Power steering (electric fault)

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Technical Power steering (electric fault)

Multiodd

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Hello,

While there are some threads on this issue I think more detail is required.

As with I think nearly all mk2 Panda, bar maybe the really early and non power assisted cars, my 1.3D 4x4 cross has the electric power assistance fitted, this is quite a standard unit used in the Panda and 500, plus some fords and other makes too.

While this unit is more power efficient than a mechanical PAS, it is delicate and far more complex and expensive to diagnose -As I am now finding :-(
The trouble is even quite well versed garages also have no idea how this thing works and cannot repair more than total replacement of the unit.

Mine is has started turning on and off, which is disconcerting when driving and brings up the consult manual error and EPS error light, the error then goes of and it returns to function, swapping between the two, though once warmed up tending to then work ok'ish

I have consulted the Panda service CD, and faults fall into 4 areas, poor power connection (it is driven directly off the battery with its own cabling), the torque sensor (a cheaper part, but will need calibration), the motor drive itself and finally the control unit M086.

My garage is advising, my error is the control unit M086, as when on test it advises its input voltage is 16.5v, while at other points in the car it is at 14v (which is normal when running). I am unsure how it can read at this level so my garage is advising to replace this unit. However as the cross has some unique features, this otherwise common control unit is only available from £700 from Fiat :-(

Does anyone have experience with this steering unit or has the circuit diagram from me to follow for it? I only have the block diagram :-(
 
We regularly get power steering questions where garages have made huge cost quotes to replace the unit. However, a reconditioned column should be around £200 and allow 2 hours for budget costs on garage labour. Another option is to get your column repaired and returned.

www.multiecuscan.net registered version (£50) has the tools to diagnose the faults and calibrate a replacement or repaired steering column.

The common fault codes are -
C1001: Electric Motor
C1002: Steering Column Torque Sensor

This covers DIY replacing the torque sensors -
https://www.fiatforum.com/panda/344792-power-steering-torque-sensor-info.html?344792=#post3427596

This is for the 4x4. I cant confirm if there is any difference to the other Panda models.
https://www.ebay.co.uk/itm/Fiat-Panda-4x4-169-Spare-Steering-Column-Electric-Servo-Power/113915101790?epid=1724733414&hash=item1a85de825e:g:MIcAAOSwnTdaPllS

This is for the ordinary 169 Panda
https://www.ebay.co.uk/itm/Fiat-Panda-169-Spare-Steering-Column-Electric-Servo-Power/112715858032?fits=Model%3APanda%7CPlat_Gen%3A169&epid=1724733414&hash=item1a3e638070:g:MIcAAOSwnTdaPllS

The 100HP uses the steering on high power by default so it might be different and the 4x4 might do the same. Unfortunately ePER is throwing one of it's regular wobblies so cant confirm if the three parts have different numbers.

Another option is repair. This is the page from ECU Testing
https://www.ecutesting.com/common-faults/fiat/fiat-panda-eps-electric-power-steering-column/

This is Western Power Steering
https://shop.westernpowersteering.co.uk/category-67.html

 
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This post contains affiliate links which may earn a commission at no additional cost to you.
Part for my 2006 petrol 4x4 is 51783676 which my ever lists at £253.90 + vat! There are other part numbers for non 4x4 but don't appear to vary by engine. A lot of garages won't properly fault find, just swap components till it goes away, at great expense. I've heard good things about ecutesting.com so worth a thought.
Another common problem which is much cheaper to exclude is the battery. This can produce all kinds of problems that disappear with a new one.
 
Hi Guys

Have you changed the main car battery yet, many times before its a low voltage main car battery beginning to reduce voltage that shows up as power steering fault due to low the voltage,

get hold of a good brand battery and see if it makes a difference first.

Tim
 
Hello,

While there are some threads on this issue I think more detail is required.

As with I think nearly all mk2 Panda, bar maybe the really early and non power assisted cars, my 1.3D 4x4 cross has the electric power assistance fitted, this is quite a standard unit used in the Panda and 500, plus some fords and other makes too.

While this unit is more power efficient than a mechanical PAS, it is delicate and far more complex and expensive to diagnose -As I am now finding :-(
The trouble is even quite well versed garages also have no idea how this thing works and cannot repair more than total replacement of the unit.

Mine is has started turning on and off, which is disconcerting when driving and brings up the consult manual error and EPS error light, the error then goes of and it returns to function, swapping between the two, though once warmed up tending to then work ok'ish

(

Hi. :)

Odd that it fluctuates..
Smacks of a poor connection :(


The first few lines you wrote are odd.

This forum has been dealing with this basic system since @2000

No.1 fault is insufficient power from the cars charging circuit.

But: in my experience once its tripped..and you have the red wheel symbol on the dash.

Only a shut down and restart of the cars systems will restore function.

I didnt see any mention of YOUR VEHICLEs history..

Alternator lifespan..and poor condition of main cables can also be factors
 
A cheap digital voltmeter wired to a cigar lighter plug will tell you if system voltage is causing trouble. My wife's car would drop the power steering when cold. I replaced the battery as the car was new(ish) to us. It seemed ok for a while but the problem returned. Later it started to get the alternator warning light which obviously affected the power steering. It would kick in as the engine warmed up but clearly not good


Replacement (used) alternator and problem solved. Its a big beast at nearly 1Kw output. The new battery was probably needed but it wasn't the real cause of the problem. A voltmeter would have diagnosed it straight away.
 
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Hello,

Thanks for the great info.

The garage guy is a good chap, fiat trained and all he does is Fiats and Alfas and particularly Pandas but more often 500's these days. He has admitted he cannot repair to electronic level, but I wouldn't imagine many people would be that experienced. He certainly knows his fiats however and has good equipment and diagnostics.

I have the elearning cd, it is pretty good, but only block diagrams of the electronics, no circuit diagrams.

I had a look at your ad and yes these things are re-conned for alot less than £480 (though you have to be wary some are just pulled out of scrap cars). And I do not think they are externally any different to one another, but the software on the ecu is different, taking into account things like the abs, 4wd and traction control etc. While I'm not sure why the steering needs to know about these different options, the different parts numbers are for these differences. The trouble with the cross it is unique in having ELD too (though maybe not unique it is an option on the 4x4?), this makes the power steering ecu for this model far more rare, if fact near unobtainable as few of these cars are getting scraped as yet.

He has found a new old stock cross ecu and motor now which has reduced the price a bit, the repairers (westernpas) would not swap this power steering unit knowing that it had a ecu fault so would not accept a return and so £125 surcharge would be hit too, they were also charging a premium for this rare model (£540 plus that surcharge as even they do not touch the ecu to electronic levels). I'd imagine someone with the kit and software could burn any version of the software onto these ecus as hardware wise they are the same -but that is beyond anyone I presently know :-(

None the less you say the power steering light should stay on if there is a fault, mine did not, it would come and go multiple times in a drive with steering getting very stiff when it did turn on? How this light goes off could show that the ecu has gone mad OR indeed the battery level is poor as it doesn't log either torgue or motor errors. The battery is only 6 months old (though a very cheap 50ah one but with no other symptoms for the car) and i've put in a new alternator to since as well due to this fault to see if that helped, but still power steering errors :-(

My alternator is 95ah over the 85 i think it originally had, this fitted fine, though if you look at the power curve it (and I imagine most alternators), produce no more power when at low revs, it is only when at high the current increases, so your not really that better off?

I will be putting a new exide premium 64ah battery in when I get the car back, its the biggest battery that will fit in the space, but with hindsight I should have done this as the first base, but the car has 111,000 miles on it, and needed new wheel bearings, track rods and inner, plus abs sensors, so was going in for these already as mot faults.
 
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The intermittent warning light could be anything but might be as simple (?) as bad wiring connection or even a chafed wire. I would get a copy of MES and run it in data-logging mode while you drive. That should give some clues as to what is triggering the error message.

What do ECU Testing have to say about it. They repair rather than exchange.

PS The 1100 has a known fault with the engine ECU plug connector which has people changing coils, plugs and all sorts. Random errors on a particular circuit often mean a wiring problem rather than blown ECU or sensor, etc.
 
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A cheap digital voltmeter wired to a cigar lighter plug will tell you if system voltage is causing trouble. My wife's car would drop the power steering when cold. I replaced the battery as the car was new(ish) to us. It seemed ok for a while but the problem returned. Later it started to get the alternator warning light which obviously affected the power steering. It would kick in as the engine warmed up but clearly not good


Replacement (used) alternator and problem solved. Its a big beast at nearly 1Kw output. The new battery was probably needed but it wasn't the real cause of the problem. A voltmeter would have diagnosed it straight away.

In this case of a faulty alternator yes a volt meter would help


I have two old cars.
I put S/H batteries which last a few years £15 plus I get £5 back on the old
I do have a volt meter in the cigarette lighter
I don't know of an easy way to diagnose a battery fault. For me its easy as I swap the batteries over



having gone through the red steering light a couple of times with each car that's four in total none are detectable by the volt meter

they measure around 14 volts all the time.

even a battery with dead cells didn't show up on the volt meter while the car is running. In fact it didn't even have a problem with the power steering although it wouldn't idle correctly but still gave out 14.1V while running although around 11.8V at rest


It may. I emphasise "may" be able to diagnose with an old style analogue meter. The needle moves far quicker than a digital meter which is far to slow. I have never tried one so can not confirm this.
 
I have just gone through a different red light problem after changing a battery.

it went worse. Every hard left or right at low revs would make fail. I suspected the new battery was faulty. Went down the motorway to charge the battery no difference.

trying to diagnose it. A few full left to right locks while holding the revs up slightly reset the system. Been working fine ever since.
 
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The alternator will hold system voltage at 14.2V even with a battery carrying a dead cell. A weak battery causes volts to drop under heavy loads at low engine revs. It's trends like that where the voltmeter gives a clue as to what's going on.

Self-evidently, a voltmeter won't help for a computer or wiring fault, but MES datalogging the body computer might show what is going on.
 
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Hello,

You mention a problem with the 1100, What is this is reference to?

I know a slightly different EPS was used on the early Panda's, this car certainly has the later type without the relay issue and fix they had. Having said that, I do hear a tick (very likely the sound of a relay from below the steering column area) that does match the on/off nature of the power steering and steering wheel light activation and then click as it turns off again?

Yes I have some concerns with the main connector that goes into the main ECU in the engine bay, not sure if it has any bearing on the present issue, but have pulled it out and re-fitted, it is certainly delicate with a large amount of connections, if that has issues god knows what you can do.

I do have a fluke meter from my old work, not tested it on the car however. The garage guy has fed back that the car have many builtin voltage checks and all come in around 14v, bar the EPS ecu that reads 16.5v?

This is his main reason why he wants to change this very hard to find cheaply ecu. As he's unsure how it can read more than anything else, other than if it has gone 'mad' in some why. Therefore a new 'old stock' ecu and motor are arriving on Monday, which I very much hope will be the end to this costly and drawn out problem :)
 
Hello,

On the alternator issue, I have heard it my not be too wise to fit a different and more powerful one to a car as with most alternators they do not produce any increased power when at idle only with the car is at a few thousand.

This extra strain at the place in the power band the engine is not designed to expect this could cause stalling / uneven performance maybe?
 
Hello,

On the alternator issue, I have heard it my not be too wise to fit a different and more powerful one to a car as with most alternators they do not produce any increased power when at idle only with the car is at a few thousand.

This extra strain at the place in the power band the engine is not designed to expect this could cause stalling / uneven performance maybe?


It will not cause strain, stalling or uneven performance.
No matter which alternator you fit, it will not cause any more strain on the engine, it is driven by a belt, the only difference will be how many amps are produced and fed to the battery.
 
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