Power Assisted Steering Error Code 01288

[nicolly130805]

Hi guys, I'm new here, I have a 2010 model fabia HTP2 1.2 Petrol. 

 

I have had intermittent PAS issues for the past couple of weeks, with the light coming on on start-up and with no assist and then going out and Steering returning to normal. 

 

However, the past couple of days light constantly on and no assist. I have checked and topped up fluid level as it was slightly low, and invested in an OBD Eleven OBD2 dongle which has thrown up 01288 fault code " Terminal 30 signal too low"

 

I replaced the battery about 18months ago and it currently has a 400CCA-45Ah battery. 

 

I have had the battery checked today and its at 72% capacity and have since put it on a battery charger. 

 

I put the battery on charge for a couple of hrs this afternoon and the light went out after about 30 secs of running but as soon as any load was applied pump cut out and light came on. terminal 30 had 9.2v, but soon dropped to 8.1v

 

I have checked the live data for the 09 central electrics module and terminal 30 is showing to have 14v ( with the engine running). 

 

However if I scan the live data through module 44 terminal 30 is only showing 8.1v. 

 

My first thought was weak battery, but not so confident now. do you think that my pump has failed? 

 

My next step is going to pull the coonectors off the pump and check the power to the pump and clean the contacts with contact cleaner. 

 

I would really appreciate some guidance. 

 

 

[nicolly130805]

so today I have done a bit more exploration to no avail. I have removed the plugs to the PAS unit and cleaned the connections with some contact cleaner, tested the voltage on the power plug which gave me 12.7v and cleaned the battery and earth terminals to the body. 

 

I have also done another drop test on the battery which showed that the battery was fine. 

 

I'm also getting between 13.7-14.1v from the alternator with all the auxiliaries running (blower at full speed, headlights on main beam and rear demist on). 

 

I'm still getting only 7.1v registering through the live data for control module 44 which suggests to me that something has died in the pump control module. the only thing I haven't checked is the steering angle sensor, but I'm not sure how to check that.

 

I did get an error logged when I unplugged the angle  sensor from the PAS pump to clean the contacts which suggests to me that the sensor probably isn't the causing the PAS issues.   

 

is there anything else I can check before I order a replacement pump? 

[Breezy_Pete]

The power wiring to the pump is the obvious problem here, not just the cleanliness of the connections. 

Not sure how easily you could back-probe the connections at the pump while plugged in and active through/past the rubber seals but that's what I would suggest.

With multimeter on dc volts setting, go looking for that missing voltage by measuring along the length of the two big cables. Positive red connection at pump to each/both ends of the strip fuse it comes from, then from brown earth connection at pump to battery negative. 

Ideally with pump loaded at least somewhat by an assistant wiggling the steering wheel gently from side to side, engine running. 

Edited 29 April, 2023 by Breezy_Pete
Sp

[Breezy_Pete]

You could also confirm/deny whether the VCDS reported term 30 voltage at the pump is factual by measuring between the two at the pump connector, back-probing while active as above.

Makes sense to do that before the above volt-drop tests, in hindsight.

Edited 29 April, 2023 by Breezy_Pete

[sepulchrave]

Worth checking the main fuse for cracking as well since terminal 30 errors usually mean intermittent power supply issues.

[nicolly130805]

9 minutes ago, Breezy_Pete said:

The power wiring to the pump is the obvious problem here, not just the cleanliness of the connections. 

Not sure how easily you could back-probe the connections at the pump while plugged in and active through/past the rubber seals but that's what I would suggest.

With multimeter on dc volts setting, go looking for that missing voltage by measuring along the length of the two big cables. Positive red connection at pump to each/both ends of the strip fuse it comes from, then from brown earth connection at pump to battery negative. 

Ideally with pump loaded at least somewhat by an assistant wiggling the steering wheel gently from side to side, engine running. 

I did put a multimeter on the power terminal to the pump which gave 12.7v admittedly not under load. Will see if I can do what you have suggested above. it seems strange that it's failed fairly quickly over the past 2 weeks which maybe led me to think that something has died in the control module. 

[Breezy_Pete]

Unloaded voltage tells you nothing except that neither conductor is totally broken.

[Breezy_Pete]

Stabbing through insulation of each wire with a needle or pin just above the cable entry grommets would be a valid alternative to possibly damaging the seals. Easily taped over subsequently. 

Make sure inserted items don't short to one another though!

[nicolly130805]

1 hour ago, Breezy_Pete said:

Stabbing through insulation of each wire with a needle or pin just above the cable entry grommets would be a valid alternative to possibly damaging the seals. Easily taped over subsequently. 

Make sure inserted items don't short to one another though!

would probing the cable with a power probe have the same result? my father inlaw has one I can borrow and should be able the test the cable under load. 

[Breezy_Pete]

Dunno; what's a power probe and can it measure dc voltage?

 

I have this vague recollection that I've seen mention of a 'repair loom' for this section of cabling (which suggests a frequent failure of sone part thereof). If you message me your VIN I can research whether it correlates with your car's age etc.

[Jocko]

You are talking about something like this https://cpc.farnell.com/multicomp-pro/mp760609/clamp-meter-6000-count-600a/dp/IN08989?mckv=s_dc|pcrid|426684131405|kword||match||plid||slid||product|IN08989|pgrid|100371162238|ptaid|pla-1824361663826|&CMP=KNC-GUK-CPC-SHOPPING-9262013734-100371162238-IN08989&s_kwcid=AL!5616!3!426684131405!!!network}!1824361663826!&gclid=CjwKCAjwo7iiBhAEEiwAsIxQEUEoh6-ffJpogKmEbYIEUGMXJYQBZbWwCr_B0t--yXHuN0uMj-mHrBoCo2sQAvD_BwE which clamps round the cable and measures DC and AC current flow. However, it only tells you the current is flowing (which if your PAS is not working it probably isn't). If you can measure the voltage under load that will tell you if you have a cable fault or if the motor is likely to be faulty.

No load voltage - supply fault (possible bad connection)

Full voltage under load - probable motor fault.

[sepulchrave]

PAS pump is a brushless AC motor so it relies upon chopper circuitry to provide the necessary square wave signal to drive the motor, it is this circuitry that usually starts to fail rather than the motor itself, often due to internal condensation build up due to imperfect sealing.

[nicolly130805]

So I have spent the last couple of weekends testing wiring and all was fine getting 12-13 volts at the socket. spoke the guys at Western Power Steering, the low terminal 30 voltage read by the OBD scanner was a sign that the internal pump circuit board had failed. ordered a reconditioned pump and fitted today and can confirm that it was in fact the pump!

 

Would definitely recommend  Western Power Steering, with V.A.T & delivery it's came out at £255 and they provide a 3yr warranty. 

 

scanned the modules to clear the codes and all good. 

[Breezy_Pete]

Well done, have you still got the old pump by any chance?

[nicolly130805]

2 hours ago, Breezy_Pete said:

Well done, have you still got the old pump by any chance?

I do but unfortunately it's on an exchange basis so need to send it back tomorrow.

[Breezy_Pete]

No worries 👍