Hi, I have a 1995 X300 with a strange power steering problem, on tickover the steering is fine but as you rev the car or drive faster it becomes very hard, I have just replaced all the flexi pipes a the were a couple of minor leaks and also had the steering rack fully reconditioned but the problem remains, we have also change the servo-tronic sensor on the rack, when unplugging the servo-tronic sensor it gets even heavier so I assumed that it was working but have since been told it could be the pump or possibly an electrical issue, does anyone know where the steering module and relay are mounted (its a right hand drive uk car), thanks in advance for any help and advice you can give.

 

Some one threw some fishing bait in the water , For RHD only check for corrosion at pin 3 ( Red wire ) and pin 6 ( Slate wire ) of the Papa Indy 61 connector below the washer reservoir filler cap . Also for RHD only Papa Indy 59 connector on left side of engine pin 7 ( same Red wire ) and 8 ( same Slate wire )

Need to determain if it is a front or rear release connector before executing repair replacing pins and sockets only and not the shell

Notice the difference on removal tool number -6 vs -5 , appears to be the some 2 prong tool used in the PI104 and PI105 engine ECU connector page 24 of doc below :

https://www.ebay.com/itm/13-Way-Male...-/131041820139

https://www.ebay.com/itm/13-Way-Fema...75.c100623.m-1

https://www.ebay.com/itm/10-x-Econos...527865/?_ul=EC

https://www.ebay.co.uk/itm/10-x-Econ...-/131125132743

See page 36 of doc below :

Hope this steers you in the right direction

 

thank you for the reply,
love the pun

 

Updated reply

 

hi all,
we have checked everything Lady Penelope suggested (thank you) but all seems ok, has anyone any other thoughts on what could be the issue,
thanks in adavance

 

I would try and find the procedure for measuring pump pressure at different rpms.

 

If the steering gets stiffer as you remove the servo connector the absence of power to the servo making it stiffer verifies that the servo works . It's the absence or diminished power to the servo we'll be looking at . This could be from a shortfall in the variable steering control module final output inside itself , the speed signal to the module , or the wiring to the servo .

At 0 speed the red wire should read 2 volts to ground ( going down with speed ) and the slate wire at 9 volts ( going up with speed )

Something is backwards here as your observation that as you remove connector the voltage effectively goes to 0 ( or the difference between the red and slate wires ) which is opposite of the pin out sheet in how it is suppose to respond getting softer as a fail safe mode .

You can read this at the Papa Indy 61 connector

Speed signal blue wire also tied into Security Control Module and Stereo bump up volume as related to speed

bad wiring mimics voltage going toward 0

A short to ground on the red wire would bias the servo to stiffer

You can unplug the stereo if that is sucking the speed signal down but not with the Security Control Module

Could the red and white wire have been crossed during repairs ? you could see this as you read the servo connector .

Ensure you have a good ground on the steering module as that lack of ground can cause problems

Editing

 

Scotland and Lady Penelope thank you both for you comments, i shall investigate further tomorrow, one thing to note is we have an aftermarket stereo installed so maybe that would tie in with Lady Penelope's comments, i will update with my findings,
thank you

 

Not to thread hijack....but is there one wire I could throw a switch in to make steering all stiff all the time at my discretion?

 

Ric , I have an idea on how to modify the system to do what you want but I'm hesitant to say based on something is backwards in the post starter's observation in removing the connector and how it should have been designed from an engineers point of view as the system should fail in the soft safe mode as the voltages goes towards 0 .

My model does not have this feature on speed variable steering servo to observe it myself

There is another consideration in putting a higher voltage on the slate wire ( 12 volts battery bus , and if it would be enough to get the desired result ) on the output of the document maker's termed transducer device in the Steering Control Module as it may damage it . The term transducer ( usually considered a sensing device in the US ) my be simply a amplifier in the US sense as an example the term alternator and generator get mixed between US and British terminology . Another complication is the accuracy of the technical writer vs. more knowledgeable engineer making the document to reference . Went though that many times with Boeing and McD aircraft , didn't have to deal with Airbus as there were alot of engineering shortfalls although they were in our fleet .

Fab , you are looking at the blue wire socket 12 going into the stereo connector as it goes into the non - standard stereo adapter connector if that is the solution , see pinout below :

 

Thank you all for your input, I will update with any finding.

 

Sorry for the late reply Lady Penelope, we have had a look today and this is our findings so far, we checked the blue wire at the stereo plug and it is not connected to anything, checked at the papa india 61 connector and the voltage is static on the red wire at 1v and static on the slate wire at 14v, neither voltages change when revving the engine,
thank you in advance for any further help or assistance you may be able to give.

 

hi all,
any more advice would be very appreciated as i'm unsure as what to try next,
thanks in advance

 

Hi all,
would anyone have any other ideas what we could try next as nothing has cured the issue so far,
thanks

 

See my last 2 post on this thread :

https://www.jaguarforums.com/forum/x...g-rack-189982/

 

Thank you Lady Penelope,
I have printed off the manual and will go through it later, I probably wont get to check anything on the car till the weekend as its too dark when I get home from work,
thanks fub