I have a 1994 XJ12 it will crank and I can hear the fuel pump kicking on, and I have checked the fuel rules, and I have a fuel in them. If I are you starting fluid, it will crank a little harder but will not start. Is anyone have anything I can check? Thank you in advance.

 

Does the tach needle move off the peg? Not sure, but I think if the crank sensor (CKP) signal is not present and coherent there will be no tachometer movement and no start.

Is your XJ12 is an X300/X305 RoW example, or perhaps an XJ81? If the latter, you might get more precise responses in the XJ40 subforum.

 

When I crank it battery meter on the dash goes down to almost 0 and I don’t know my car says it’s an XJ 12

 

There is a specific relay for the fuel injectors on the V - 12 for the X300 , not one for the X40 ( X81 )

See page 17 , large # 5 right for the X300 ( X305 ) chassis

X300 1996 LWB.pdf (jagrepair.com)

is yours a X40 ( X81 ) or X300 ( X305 )

Do you know the manufacturer of the engine ECU ?

See page 18

801S TITLE (jagrepair.com)

The headlight are not necessarily a tell so would have to use the VIN #

There was some X40s built with round headlights from my understanding

 

When the starter solenoid relay closes providing power to close the starter solenoid and the resulting voltage result is not enough to properly run the engine ECU hence injectors are not commanded to cycle open

You can easily swap out the starter relay but probably wouldn't give you anything , but a easy try to cover that base

The medium gauge wire from the starter relay to the starter solenoid can be checked but with such a large voltage drop ......................

This will be the wire attached to the side of the 2 large terminal post on the solenoid....

The at the solenoid large pigtail wire to the end of the starter electric motor portion if grounding could provide enough voltage drop for your observations

Last step replace the starter

A loose connection through the wire group would not cause a large starter voltage sag

It would on electrical power generation / alternator

 

Need to know model of chassis to go through the battery cable connections from the battery to fwd

Do not over tighten the battery positive post , breaks the nut underneith

 

I'm sensing that there might be too much technical jargon about chassis codes flying around here to get you helpful advice (I should know, I've been yelled at at brunch for doing the same thing!) Even if your car is an XJ12, this might not be the correct sub-forum for you. To determine this, I'd suggest you Google the following phrases:

• Jaguar XJ40
• Jaguar X300.

If your XJ12 looks like an XJ40, I'd suggest you direct your question to the XJ40 sub-forum. If it looks like an X300 you're in the right spot! It's a little confusing because even though the X305 XJ12 was technically 1995-1997, some (mine included) have 1994 production dates. The ignition systems between the two are pretty different and to get you the right answer, we'll need to know which generation of XJ12 you have.

 

Xj40 sorry I was gone for a few days

 

How do I move this thread to the xj40? Sorry.

 

See page 21

94 XJ12 Sedan Technical Introduction S81.pdf (jagrepair.com)

and page 30 . figure 6

93 XJ6 Electrical.pdf (jagrepair.com)

Fo r future reference on the V - 12 version of the X40 being a X81 variant has a 2nd fuel pump relay module in the trunk right area on the XJ12 Sedan Intro document in the relay map page 40

See page 18 paragraph 2 with illustration pic of the XJ12 doc

 

How do I test it like how do I know for sure for sure is that

 

Is this your instrument cluster ?

Do you drop to or below 9 volts starter sag ?

Tme to move over to the X40 section with a new thread



This pic is of the similar X300 version but notice the markings

 

Yes, it does drop below nine

 

Bad battery IMO. You need more than 9 to crank

 

It’s a brand new battery and it matches what is necessary for the car for cold cranking, amps and cranking amps what can I do to fix it or what can I do to fix the starter stag?