Jaguar Xjs 5.3 versus 6,0 V12 Throttle Position Sensor

Does anyone know if I can easily use a Throttle Position Sensor from a 6.0 year1996 to a 5.3 year1984?

Unlikely to work, but it might. The 6.0 TPS has voltage at idle set around 0.6 V, while the earlier version calls for 0.3 V.

Here is the parts TSB we got when I worked at the dealer.

C-11 Throttle Potentiometer.pdf (333.0 KB)


I’m pretty sure they’re the same except that the 6.0 has two position sensors in one, the second to communicate with the electronically-controlled transmission. You can just ignore that one, just connect up the one you need.

Yeah, but I believe that’s going from early 5.3 to later 5.3. The 6.0 is different yet, having six wires instead of three.

As Steve mentioned earlier, the required set voltage on the 6.0 litre unit is double that of the 5.3 and yet the ECU output voltage is the same at 5 volts so something is not going to work correctly, or am l just missing something?

Why don’t you just turn it round on its mount 0.3v more than the other one? How will the ECU know the difference?

It’s just a potential divider, splitting the voltage across the two ends.

kind regards

I don’t think there is “room” to turn it. Adjusting the two screws doesn’t seem to allow 0.3V move IIRC.
In addition, the TPS part# DBC2626 is NLA and nearly impossible to find.
The early TPS is at least still available – why go through the trouble?

And why not a hall sensor as described in the Book ?
Less expensive and will last forever…!

In that case, just add a small resistor at the 0v end so the centre terminal default voltage is at the required level.

This all assumes you are looking to replicate the three pin potentiometer - the early pre-HE had a more complicated arrangement.

kind regards

When I asked if the potentiometer from 6.0 1996 could be used for a 5.3 1984 was because I already have a potentiometer for a 6.0 and would like to avoid buying a new one for my 5.3 1984 if it wasn’t necessary. I bought a 6.0 sedan for scrapping to have spare parts for the 1995 Daimler Double Six. As you probably know, it may be difficult to get parts for 6.0.

In that case Marek’s idea to add a resistor is a good one.
On the other hand Jaguar’s TSB says it works without any modification…?

My bad, apologies. My post #2 in this thread probably took it off-target. You have a spare TPS form the 6.0L V12 that has the Nippon-Denso ignition system used in the XJ12s MY '95-'96, not the Marelli that was used on the XJS’s.

This means you have this, part # LNA1660A

This TPS is not the same as DBC2626 mentioned earlier. I have no idea what it does at idle and WOT.

I am sorry I misread the OP.

The TSB given by Bob does not describe the 6.0L V12 TPS.
DBC2626, what I have on my '95 6.0L V12 with Marelli ignition looks like this:

One will notice that EAC9634 which is what the 5.3L V12 has a small keyed shaft, while the DBC2626 has a hole and mates to the much bigger and fatter shaft in this way (I am sorry it is just a parts diagram, I did not take good pictures of the disassemble part):

More importantly, you’ll see four wires not three. You’d want to know what that means.

It looks like perhaps the WOT mixture enrichment switch may be on the potentiometer and not as a separate switch bolted to the assembly as in earlier cars with a 16cu - studying the relevant wiring diagram may be of assistance here.

kind regards

Idle switch (if this is what you mean by WOT enrichment switch) – part # DAC10181 is a separate beast:

My guess is that since the Xj12 was OBD-II compliant and likely uses CANBUS, the 4th wire is serving this purpose.