3.0tdi heavy steering - help

SteveMcB

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Twice in the last month my steering has been very heavy at start up. After driving a short distance then switching off and on a couple of times it was fine. Fluid levels look OK , does anyone have any ideas?

PS this is going to sound daft but the first time it happened was after resetting the service indicator ( i had to reset it again to get the servotronic working) then for a few weeks everything was fine until I paired a new phone, even more weird was that once I turned the blutooth on the phone off it went back to normal!

Can't think how these could be connected, any ideas before I pay for a scan?
 
Simple things first, oil level okay?, drive belt okay, not shiny and no cracks on the grooved side.
Any leaks onto the drive belt, causing belt slip?
All pulleys running in line, look down from above with a torch when engine is running.
Theres loads more things, but thats the basic stuff covered.
 
Ta, levels and belts look fine, no funny noises from the rack or sounds of slipping, it did it again this morning but this time servotronic would mot come on until i had done about 5 miles and did a quick restart. A m thinking it is more likely electrical than mechanical, does anyone know if a faulty relay could cause this?
 
What is servotronic?, some sort of parking aid?
Have you had battery tested, clutching at straws i know!


Lynall
 
What is servotronic?, some sort of parking aid?
Have you had battery tested, clutching at straws i know!


Lynall

Servotronic is the brand name of the variable assistance power steering used by BMW, Audi and others. In essence, it provides more assistance (i.e. lighter steering) at parking speeds and less assistance (hence heavier steering) thereafter.
 
So more electronic trickery to go wrong!
Im guessing theres some sort of electric/hydraulic valve that control the flow/pressure of the oil?
 
Just looked on partbase, all the pump side is std gear, the servotronic bit is built into the rack itself, they also list non servotronic racks.
There is a pic of a short loom down to the rack itself.
 
Thanks, electrical trickery is right. Battery is fine.
TPS. quoting £111 plus vat for a new servotronic control relay :( going to get it scanned first.
Does anyone else have experience of this, it's doing it every morning now, think the service light/phone were pure coincidence.

I can only find one other thread and the symptoms are a bit different from mine
 
Well if its a rare fault that means a second hand relay could be a good bet?
 
Had exactly the same issue on mine. Turned out to be the servotronic relay/module. I sourced a second hand one from eBay for about £15. As it was from an A6/A8, the characteristics of the steering were different. It made my steering heavier sooner than usual (which I actually prefer).

If you know anybody with an Audi with servotronic nearby then it might be worth swapping modules to see the outcome?

Azeem
 
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Had exactly the same issue on mine. Turned out to be the servotronic relay/module. I sourced a second hand one from eBay for about £15. As it was from an A6/A8, the characteristics of the steering were different. It made my steering heavier sooner than usual (which I actually prefer).

If you know anybody with an Audi with servotronic nearby then it might be worth swapping modules to see the outcome?

Azeem

I remember that episode. It seemed to consume your life for about three months before you cracked the case, didn't it?
 
Thanks Azeem,
There are a couple on ebay just now, a B7 one for about £60, the A8 ones are a lot cheaper so will maybe go for one of those. Fingers crossed,
cheers
Steve
 
Will do, just got to decide which module to go for now.

incidentally mine seems to be temp related as well, if I keep the module in the house overnight it works fine, just need to decide on whether I should maybe move further south
 
Can you not open it up and look for a dry solder joint?
 
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Actually thought about opening it up but TBH would't have a clue what to look for. Azeem's link shows an internal view which has put me right off that idea. I'm going to see if my RAC warranty will cover a new one but will keep checking on ebay in case a 640 or 605 (none on at the mo) come up at a sensible price.

It works fine when warm so I'll keep it indoors overnight or maybe see if I can find a wee fleecy jacket for it :)
 
Had a look under the dash today and turns out I'm using the 392 control module and not the 605.

TableOfServotronicControlModulePNs.jpg
 
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Thanks very much for going to that trouble, much appreciated.
Given the choice i would prefer the steering to be slightly heavier than stock, ie a module that gives about half the assist of a 640, i wonder what the one from the S4 would be like. There are a couple of 356s on ebay just now but have no idea what they would be like. I'll hang on until the warranty people make a decision before diving in
 
Thanks very much for going to that trouble, much appreciated.
Given the choice i would prefer the steering to be slightly heavier than stock, ie a module that gives about half the assist of a 640, i wonder what the one from the S4 would be like. There are a couple of 356s on ebay just now but have no idea what they would be like. I'll hang on until the warranty people make a decision before diving in

No trouble at all pal, was changing the clutch switch anyway. :icon_thumright:
 
Quick update. Bad news is that I had to part with £133 for a new 640, good news is that after a bit of wrangling - is it a module? (not covered) is it a relay? (covered) - my warranty company have agreed to pay for it. Also covered 2 new reversing sensors so I'm well chuffed.
 

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