Hi recently posted about my xj-s not running on 12, it has been sitting since 2000. I have just tested the supply pulses to the injectors and found 1B, 3B and 5B and not receiving any voltage. Any ideas??

Much appreciated.

Nic

 

Well done.

1.3.5 are ONE group of the injectors.

That leads me to the Resistor Pack terminals that Greg in France has done an excellent write up on, just below your thread here. "How to service the V12 resistor" is the title.

Next would be a broken wire in the loom, usually under the a/c compressor.

Followed very closely by the EFI loom being toast, which is getting "normal" now with age alone.

Here is a schematics related to our market that I use regularly.

V12 EFI schematics Australian cars.pdf

XJ-S ECU Pinout table.doc

 

Voltage supply to the injectors comes from the main relay. With the ignition on (do not start) you should have 12volts on BOTH pins of the injector.

If you have no voltage on either side then check wiring and connector, the resistor pack is not being used at this point.

If you do have voltage then check the connector and resistor pack.

 

Thanks for the replys, as far as I know my car being a pre HE does not have this resistor pack. I will have a closer look and check the connections and for any cable damage this weekend. Out of interest does any one know if possible or where to find new power amplifiers , ecu , and ignition amplifiers? Or am I best looking for good second hand parts? Here's hoping I don't need to purchase these but it's good to know if they are available.

Cheers.

 

OOPS.

That is why the vehicle should be mentioned, anyway, no harm done, you can buy the drinks when we meet one day, HAHA.

I would be following Warrens suggestion as to 12v at the injector plug of each injector. If there is NO 12v then a broken wire will be the culprit.

If it comes down to a pulse fault, then the trigger board inside the distributor is #1 on my list.

Here is some stuff I have on the D Jetronic system. There may be some duplications, but a Kiwi can sort that quickly.

D Jetronic 1.pdf

D Jetronic 2.pdf

D Jetronic Injector wiring from the amp.doc

D Jetronic Jaguar info.doc

D Jetronic wiring 2.pdf

D Jetronic wiring diag 1.pdf

D Jetronic wiring legend.pdf

Have fun.

 

Regarding the amplifier, etc: you might want something called ReOpus from SNG Barratt. It's not cheap, but solves all Lucas Opus issues and looks like stock.

SNG Barratt - The Ultimate Jaguar Parts Specialist

 

Excellent thanks grant, I'll let you know how I get on. Beers on me if you make it down these ways.,

 

Thanks for the link, I'll do some more trouble shooting first.

 

Hi so I have done a voltage check, and found 0v on both terminals of injectors 1b, 3b and 5b. I had continuity between the terminals and the connector, so I cleaned the connectors and now have 12v on 1 terminal of the injectors and nothing on the other (o/y #7 ). I will do some more cleaning but I suspect my connector block has seen better days. Does anyone know where I can find new replacement parts? I would like to redo as much of the wiring as possible as I can see It causing problems down the track.

Cheers

 

Nick,

Its been years, too many.

When I did Sir Arthur, the S2 V12, I used Narva Loom connector 56278BL, which is an 8 wire unit. The loom in the V was renewed and lifted up to run down the injector plate bolts.

The wiring from teh front amp to that connector were OK, just the engine side was crap.

One wire at a time as I had no books, no Forums, nothing, so seat of the pants stuff, and being her car, the blow torch was already burning, trust me.

 

So Iv done some more digging, although my injection cables are original they all seem to be in ok condition, no breaks anywhere and still have a reasonable amount of flex. I will upgrade at some stage, but for now I opened the amplifier up and found I do NOT have 12v at terminal 7 (oy) inside my amplifier. Are there replacement parts available? pots etc... or should I be looking for a new amp? Cheers 🍻

 

Problem solved guys, I had a faulty transistor in the EFI amp supplying cylinders 1,3,5 B. $6.35 and some soldering and the big cats running on 12. Thanks again for your help!

 

Good find, Those power transistors are pretty robust, I would check the current draw on that circuit to put my mind at ease that the failure wasn't caused by excess current draw.