JaguarSport Zytek ECU ID

Hi folks, found this thread through google and wanted to post a pic of a JaguarSport Zytek ECU I have to see if anyone here can ID it. This came to me as part of a large group of parts, mostly non-Jaguar.
JaguarSport part number is SPD1026, Zytek type is R1-0-12. I haven’t been able to find any reference to these part numbers online.

The ECU also came with a wiring harness including injector connectors labeled 1A - 6B (so twelve injectors total). There is also a Lucas 73348 throttle position sensor and actuator/bracket assembly connected to the harness. This to me looks like a XJR-S or XJR15 part, based on looking at engine photos of both models. Construction of the harness is exceptionally nice, with a large 30 pin Cannon plug to connect to the ECU, full Raychem heat shrink and labels for every

So any thoughts about what this is for? I initially thought XJ220 but ruled that out as the TPS and bracket do not seem correct. I know very little about Jaguars in general so I’m hoping the experts here may recognize it.

I’ll post an image of the wiring harness in a different reply as this forum seems to restrict how many images a new user can post.


As the XJ220 only had the V12 in the development car(s) it’s probably a safe bet that its not for one of those cars.

This harness is very similar to the one installed in my 1987 6.4 TWR with Zytek ECU and multi pin connector. My car has an extra loom running to the fuel pump relay in the boot and the speedometer pulse converter. Very interesting, what’s it from?

Bill Sent this from his iPhone

Bill, I wish I knew what it was from. Hoping someone here can ID it and the associated ECU, see my previous reply about the ECU.

Robin, understood about the XJ220 having a V6 rather than a V12. However don’t those cars have dual injectors per cylinder? In which case, 12 injector connectors on the harness would make sense? That was my initial suspicion. Regardless, the TPS and associated hardware doesn’t seem to be appropriate for an XJ220 from the pics I have seen.

Can you show a close up of the multi pin plug and I will compare with mine.

Bill Sent this from his iPhone

Sure. Left is the ECU side, right is the engine harness side.

The connectors look identical to the ones used on my development car, tomorrow I will post pictures of my ECU connectors and ECU model

Bill Sent this from his iPhone

This is the Amphenol connector on my Zytek system, I think your engine wiring loom will be the same as mine but the loom from the engine bay through the bulkhead to the ECU in the footwell will not have the same ECU connector…I think yours is from a early 6 Litre XJS Jagsport/Facelift V12


The Zytek Type Number R1-0-12 is the same I find on my 1989 UK only (Jaguarsport 6.0) Zytek ECU. But is has as following Number 725-00154. I am sure because this is what I get by reading out with the Zytek software.

I guess the Jaguarsport Part No might also have a correlation to the software installed.

The Zytek software (file name: FBDPB232.EXE), which is named Version 3.32 from March 1990 shows on the second screen configuration to use with Jaguarsport ECU NO. SPD1062.

So this could be a hind on the year the ECU has been first programmed.

It would perhaps be helpful if you read the software status with the Zytek diagnostic tool. THis will give you the required information on program and data identification (I have a German software version). In my case I also got the information for what car it has been programmend (1989 UK only…).

Your harness is different to what I see in my car or on ebay for newer harnesses. Also I can only see one water temp and another pair of wires perhaps Intake air temp. You should be able to read the labels. Afaik the XJR-S always hat two intake air temp sensors. These wires are not on your harness? But please correct me if I am wrong.

Here a “screenshot”

Hi Markus,
The harness does have two 2-pin connectors marked “AIR(A)” and “AIR(B)”, located alongside the #3 injector connector on each side of the harness. We also have “POT” (3 pin connector for the TPS), “IGN” (two wires near the TPS), “DIST. SYNC.SPD” (4 pin connector near INJ4A), “WATER” (two bare wires near the Amphenol connector, presumably water temp) and finally “A” and “B” (two white 10 pin connectors, populated with 8 terminals, branching off near the Amphenol connector). On the ECU side, in addition to the other half of the Amphenol connector we have a “DIAGNOSTIC SOCKET” (5 pin circular connector) and an unlabeled bundle of 4 cut wires.

I’ll have to do some research about what kind of interface I’d need to use to communicate with the ECU. I’ll admit that I haven’t read the entire previous Zytek thread and maybe it’s time to do that now. Is it a DOS program communicating with the diagnostic port over a serial connection?

I’m in the vintage car parts business and deal with some electronics stuff, but Jaguars are completely outside of my area of expertise. At this point my goal is to ID this so I can get it into the hands of someone who can use it as a spare.

Also, do you think the “725-XXXXX” number is just a serial number, rather than anything related to the type? That was my assumption, as the latter part of the number is printed on a small paper label.

The two white 10 pin connectors would go to the injector resistor packs, and the cut cables would go to the boot and connect to the fuel relay, ignition relay (for 12volt supply) and supply pulses to a Zytek 10-1 multiplier for the speedo and dash trip computer. It would indeed be a useful harness and spare ECU. I wonder why it has been detached from its V12?


Does your ECU have the Amphenol Connector as shown on Bills picture? From your Picture shown on post #1 I can see the 60pin Connector as I know from my own ECU. Does the harness belong to this ECU or is in your case the ECU harness equipped with a 60pin socket on the one side and the Amphenol connector on the other side (as shown in your hand on the picture)?

Could it be possible that the donor car might have a ECU problem in his history and after an ECU crash they delivered a new ECU with 60pin connector and a special ECU harness?

In the end for your business it would be helpful to read the software version and do a snapshot of the tables from the Zytek diagnose tool, and perhaps of the real time values even only connected tool to show that at least the Map Sensor is working….

To get hold of the Zytek diagnose tool is difficult. Someone uses the word “unobtainium” for the connector ECU - Computer. You will find information in this forum which mentioned only 24 -27 System build worldwide?!

“725-XXXXX” as serial number would make sense but I do not know.

Hi i have this Zytec diagnostic kit for if of any interest.

Den fre 24 feb. 2023 10:36Markus via Jag-lovers Forums <> skrev:

Den fre 24 feb. 2023 10:36Markus via Jag-lovers Forums <> skrev:

Den sön 26 feb. 2023 16:32Petri Laukkanen <> skrev:

Are there any more disks with it?

Hi, there is only one unused floppy disc with XJ220 software on it, however i believe that there are several people in this community that are in possession of various software suitable with this kit for Zytec eqiupped vehicles like XJRS 6.0 etc.