No power steering. I think I've tried everything - Looking for advice.

[Boyjan]

Hey guys,

 

In my infinite wisdom, I purchased myself an '06 Fabia Combi 1.4TDi (BNV) with faulty power steering, thinking it was going to be a cheap and easy fix. Boy was I wrong! It doesn't take much effort on Google before you realize that this platform suffers it's fair share of issues with power steering and I have to admit that I've hit a wall while troubleshooting this thing. Here's hoping you guys can help me out!

 

As mentioned, the power steering was out when I bought the car and the PAS light was on.

 

 - Fluid level is ok

 - There is no communication with the PAS ECU

 - Fuses are ok and there are no hairline fractures on the ones on top of the battery.

 - Battery is solid and charges at a healthy 14.3V

 - Pump is supplied with 12V+ via the big connector

 - Both wires from the alternator were snapped. These have been repaired

 - All earth wires I've found have been properly fastened and free from corrosion.

 

Still nothing. I've now swapped the pump from a car that, although the PAS light was on, had functional power steering. Still, nothing. Completely dead.

 

The pump originally installed in the car has part number 6Q0 423 155AJ

The one I've just fitted is a 6Q0 423 155AM

 

If I've understood things correctly, there are mainly two PAS systems installed in the Fabias of this era distinguished by their steering angle sensor workings. I believe these might differ due to the donor car being from 2000 or 2002 and the other being a 2006, but if that was the case, I should at the very least get limited steering assistance, right?

 

Any help would be highly appreciated, as I'm about to go at this thing with a steel pipe.

 

Edited 30 October, 2018 by Boyjan

[Breezy_Pete]

No communication points towards a problem with the ignition 12V feed or the CAN wiring, I think; both on the left hand 4-way connector in this picture. I guess the first thing to see is if the ignition 12V is present, on the black/yellow wire when ignition is switched on.  I'll just check what fuse that ignition 12V comes off, as I think it's shared with one or two other things.

[KenONeill]

@Boyjan - I'm not being funny, but have you checked fault codes? I would not be surprised to find one with a narrative like "Steering Angle sensor - implausible value".

[sepulchrave]

No communication with the PAS means no fault codes, I suspect you have a combination failure of both the pump and the angle sensor, try swapping the sensor from the car you took the pump from.

[Breezy_Pete]

Fuse 7 in the cabin, I think, shared with MAF sensor.

[xman]

Is the pump spinning at all?

 

First thing to always check is the battery. Even though its charging at 14.3 volts, the battery may be knacked and the PAS getting disabled at start up.

 

Whats the terminal voltage after car has stood for an hour or two. Then measure it with ignition/headlights on but before you start.

 

Any chance you can try another battery or at least charge it fully.

[Boyjan]

Update: I'm a jackass!

 

Went out to have a go with your suggestions and when I got to the point of checking for ignition positive on the pump CAN connector, I noticed it came off way too easily. Anyone that's dealt with these pumps (or VAG connectors in general) know that they can be an absolute pain in the ass to get off. Hmm, tried pushing it firmly down into the recess until I heard it snap into place, started the car and lo and behold: No PAS light and the car has power steering!

 

That'll teach me to do things right the first time round.

 

Thank you for your all your input, guys! Beers on me

Edited 31 October, 2018 by Boyjan

[Breezy_Pete]

Result.

[xman]

As with so much in life, its usually the simple stuff. Is it plugged in? 

 

[LB123]

Quote

faulty power steering, thinking it was going to be a cheap and easy fix.

Doesn't get much cheaper and easier than that!

[AlexFabia]

Connector issue I assume? I had to change mine as they were corroded and it fixed the issue. Sadly many shops don't know how to interprete the fault codes (or lack of them).