Sorry to post such a seemingly dumb question.

A few weeks ago after a heavy storm when the alarm went off I got failsafe mode and code P1122. Graham (GGG) suggested a dud battery which after investigation seemed very likely. Put a new one in and all was fine until this morning when got failsafe and P1122 immediately on startup. After 3 cycles of starting codes and warning cleared and drove perfectly into work. I know battery /volt were spot on so I'm thinking maybe it's the TB sensor. Forum advice is to clean the TB connector first but I don't know where to look to find it

A photo or diagram of it's location on my 2001 XKR would be very much appreciated.

Thanks

 

To answer your question. The Throttle Body (see item 3) is at centre rear of the engine:


(click on the image to enlarge it)

P1122 fault is:
Pedal position sensor circuit “1” low voltage

Possible causes are:
1. Pedal position sensor to ECM sense circuit “1” (sensor pin 4) wire open circuit or high resistance
2. Sensor power supply fault
3. Pedal position sensor failure

Graham

 

Thank you Graham - appreciate it.

Steve

 

Located the TB connector but can't remove it from the TB. I'm actually at work so loath to put on to much force in case I break it and end up stranded?
There is a flat plastic "tang" on the back of the connector that looks like it needs to be depressed but I still cant wiggle the connector free.

Any tips for a dummy?

In the meantime I've sprayed the connector block with Servisol switch cleaner just in case there was some damp/moisture inside

 

Steve,

This is my 2001 Normally Aspirated XK8 but I assume the SC Throttle Body connectors are the same:



The Throttle Position Sensor connector is locked by the plastic tab arrowed in blue going over the one arrowed in red.



Slide a thin bladed screwdriver under the blue one and this will lift it sufficiently to release it.

Graham

 

Thank you Graham - now I'm feeling even dumber because I was trying to remove the wrong connector!
I had misidentified the TB connector as the one below the throttle cable spring on the other side of the TB (right side of engine looking from front).

Now you have corrected me I'll definitely leave this until I'm back home (cant remove the intake manifold here anyway).

Are there any hand household tips to minimize my chances of FUBAR?

I've read threads here that the TB may need replacing/rebuilding and that there is a factory recall for mismatched connectors.
My VIN ends A16249

Thanks again Graham
Steve

 

Steve,

The usual problem with the Throttle Body is the TPS fails. Several members have tried to find a source for replacements but I don't recall reading of any success.

When mine began to give problems on a 2001 XK8 in 2011, I was able to clear the code a few times before it became terminal within a few hundred miles.

steveinfrance dismantled the old TPS to determine the cause of the failure and found a break in one of the tracks but wasn't able to carry out a reliable repair.

Graham

 

As it's been some time since I looked for a replacement TPS, I thought I'd have another search. This ebay link could be useful:



Throttle Position Sensor for 99 02 Jaguar XK8 99 03 Jaguar XJ8 198500 3250 | eBay

Graham

 

Thanks Graham.
If this turns out to be the case with mine then is it ok to simply replace the whole TB? I see they come up on ebay for a few hundred quid

 

Thanks for the link Graham - I presume if a new TPS is fitted then it needs uber accurate setup or do they just bolt on? If the latter I think I'll just buy one in case.
The vehicle compatibility check says this wont fit the XKR but maybe this is incorrect as it fits the 2001 4.0L XK8

 

Steve,

I got a used replacement TB from Eurojag in Darlington who will probably also be your closest source.

The TPS has rotational adjustment so it's not just a simple bolt on.

Graham

 

Thank you Graham - as I suspected.
However, I presume that if I source an appropriate TB that would be a simple bolt on replacement that I could get my indy mechanic (Jag trained) to do?
Steve

 

Graham
I have managed to find the part number for the TB (C2A1445) but can't find the TPS part number for my 2001 XKR. I've found that DENSO198500 3250 is for a 2001 XK8 but not certain that this will fit the supercharged engine.
Do you perchance know the correct PN?

Thanks
Steve

 

Just came across this
I found it helpful - esp about having to hard reset after any and every TPS position adjustment.

Now I've seen this i'm a little less nervous about removing and cleaning the TPS but think i'll wait until I've got a completely free weekend!

 

I took the TPS and PPS connectors apart yesterday. No sign of any moisture, corrosion or loosening. Couldn't really see whether the TPS harness connector had the newer gold pins or the older tin ones - it certainly hadn't had the factory recall retrofit gold pins - the connector on the PPS definitely had gold pins. Gave them all a really good soaking in electrical contact cleaner - the little brushes you can get to clean in between teeth/crowns are perfect for cleaning out the insides of the female connectors by the way.

Anyway, so far so good but it's to soon to tell if this will fix the P1122 issue. My gut tells me not and I'm on the hunt for a replacement TPS for when the current one packs in all together.

 

If the throttle body is the same part number for xk8 and xkr then the tps will be the same.

I will be interested to know what you find out for when my tps packs in.

 

Good point, the TB part numbers are different for XKR and XK8

 

Take a close up pic of your oem tps and see if someone can confirm it's the same as the one on a XK8 from the same year. They must have some sort of number on them.

 

Yep - trouble is I think I'm going to have to take it off the TB before I can read the part number on the TPS - I'll take another look with a dental mirror and see.

 

It's DENSO 198500 - 3250

Same as the XK8