Here is the simplest improvement you can do for your XKR steering.

Remove driver side fuse #10. Power steering goes into low power mode although you also lose climate control. Easily reversed.

I have been running this for nearly two weeks and it is a COLOSSAL IMPROVEMENT, especially over rough pavement in daily driving.

Thank you to the Jag Wrangler who informed me directly of this in response to my inquiry about his delayed adjustable steering power project. He also sent instructions for creating a simple on off switch so I could retain climate control and keep the heavier steering. My Jag mechanic has agreed this is one modification he won't veto...

 

Could you please post the wire schematic I would love to try this out...

That's the number one thing that makes me MAD every time I drive the car, that loose steering at in town speeds, I can't stand it.....

 

It is actually fuse #12 (not #10). Try it with the fuse first and see if you likely before doing the mod.

I will post it later. It varies slightly for different model years.

 

If I remember it is the blue/white wire on the servotronic relay that you splice into. You cut that wire & run it to a toggle switch. It was a very common upgrade years ago on the X100.

 

Does this apply to the non-R cars?

 

Yes, all XK8/Rs.

It basically causes the variable power sterring controller (ZF Servotronic system) to see a fault. The default behavior for the steering system in the absence of an operating electronic controller is to provide some assist, but a fixed minimum amount. Since the system is not tied to the internal communication link on these cars, it does not display any fault messages.

 

So, which is fuse 12?

 

In the fusebox between the dash and the door (US driver's side), left column, 3rd fuse down, red 10 A fuse. If you look closely the numbers are embossed on the black plastic.

 

It also makes the steering a lot harder in parking lots. Tried it before, not for everyone. Feel was improved over 15 mph though

 

Absolute genius!

 

As JGAXKR mentioned, this mod. has actually been 'out there' for a number of years.

Experiment with it first by removing the fuse. Since the climate controller is on the same circuit, this will also disable all the climate control functions, so the fuse removal is just a trial method to see if you like the feel of the steering.

If you decide you want to make it permanent, you can put back the fuse and add a switch just for the steering mod. In one position you will have the normal variable assist steering, and in the other position you will have the fixed minimal assist steering.

See Paul's wiring description in the post below. The steering module has a 9-pin connector behind the glovebox.

You can then locate the switch in a convenient place. Probably the best spot is either the 1x1" vent on the left side of the steering wheel (which is a blank),or in the coin tray or inside center console cubby.

 

Actually, if you place a Switch in series with the Speed Signal, the switch will either allow normal (Variable Boost) Steering or, if the Switch is open, High Boost (Low Effort at all times).

If you want the Switch to switch between Normal operation and "Always Low Boost" (Always High Effort) Steering, you must interrupt the 12v feed to the Module (Pin 6 on the Module).

In my case I want HIGH BOOST (Low Effort) at all times, so I just disconnected the Speed Signal at Pin 4. The Module then applies full voltage to the Rack Solenoid at all times.

(The solenoid on the Rack will default to High Effort if No Voltage is connected to it.)

 

Thanks for the correction Paul. I should have checked it out before posting.

 

Brings up a interesting variation that would permit all 3 modes.

By using a DPDT Center Off Toggle Switch you could interrupt both Feeds to the Module.

One Off-Center position would allow Standard Operation.

The Center Position would Select "Always High Effort" Operation.

The other Off-Center position would Select "Always Low Effort" Operation.

 

Sounds like a job for **fanfare please** the Jag Wrangler. A pre-wired switch designed to fit in the blank vent next to the steering wheel for all of us electrically challenged folk. Might be enough interest to justify this product.

 

Nice segue Mike .

What I really have planned is a module that lets you customize the speed variable steering to your liking using the cruise control buttons and possibly the instrument cluster display. Basically you will then retain the speed variable feature, but the speed vs. steering assist curve will be alterable on the fly to the driver preferences.

Interest so far has been lukewarm, so I postponed the project for a while....but I still intend to do it.

 

Steve,

Sounds like an even better upgrade. The dial-in approach would certainly be more appealing and I would be interested. So consider this another vote to move this up on your list?

p.s. still saving my nickels for the remote convertible product. However, a new set of tires has to come first.

 

So I'm guessing that you would intercept the speed input line and modify what is sent to the controller. Hopefully this is a DC voltage that is proportional to the vehicle speed......correct? In which case this should be fairly straightforward

 

The Speed Signal is a 12v Pulse Train.

10mph = 20Hz
20mph = 40Hz

This Probably results in a Variable (Pulse-Width-Modulated) 12v Signal at the Rack Solenoid.

 

The speed signal is actually a Frequency Modulated digital stream, but a similar idea. It should not be too difficult. I was thinking of having two basic modes:

1. A few preselectable lookup tables with some common speed to assist mappings.

2. An on-the-fly mode where you can change the assist level up or down directly (unrelated to speed) with the cruise arrow keys.