Hi All,

New here abd tried searching but did not find any info. Suddenly, the top on my 1994 xjs 12cyl no longer operates. There is power at the fuse. But no power at the motor. Does anyone know if its one of those relays I see back there?

Any help would be hugely appreciated!

Many thanks.

 

There are two relays, one for top up and one for top down. They are located in the boot in the tray above the battery.

There are 6 relays there, the two in the middle control the top.

Cheers,

Allan

 

Any chance someone has replaced their motor? What sort of fluid does it use and how do you fill it?

Many thanks again!

 

It uses hydraulic fluid, the spec is for Univis J13.

One other thing to check, there is a switch on the motor/pump body that controls electric or manual operation of the hood. Make sure the arrow is pointing to electric.

Also, and I'm sure you already know this but you do have your handbrake on and the brake light on the dash is lit right?

Cheers,

Allan

 

And don't forget in park or Neutral too

 

Hi,

Thanks for all the feedback so far.
So, I am in park with the hand brake up and I removed the relays and used a test lamp to check things out. Seems like there is power to the relays but when the switch depressed there is no power to the motor. I jumped a relay and heard some faint sounds from the motor but no movement. Also, with the motor disconnected there is a slight dimming on the lights (interior and exterior) when the to switch is depressed. I think this means that there is an electrical load onto something. Could the parking brake be the culprit?

Thanks as always.

Ed

 

Allan, it appears you and I have the same car and I have a similar problem. My top goes down fine but will not go up automatically. I can put it manually without any trouble and the windows roll up fine.

Any thoughts on this?

 

My 1993 roof would not operate unless the emergency brake was on. Not sure it is the same on your 94 but it is worth checking.

 

If the rear windows go up then your switch in the console is good. My first inclination would be to check the "Top Up" relay. First you could swap it with the "Top Down" one and see if that alters things. Then check the relay base to make sure you have 12v on pin 86. Also check pin 85 to see if it changes state when the switch is pressed. If all that fails then check pin 3 of the control module to see if it changes state when the switch is pressed. If it does then the problem is in the wiring between the module and the relay. If it doesn't you might have a bad module. Unplug it and clean the contacts and see if that helps.

One final thought, have you checked that the hydraulic fluid in the pump/motor is topped up?

If you haven't already you might want to download the electrical guide for the car, just go to the "how to" link at the top of this forum and click on electrical diagrams.

Cheers,

Allan

 

Is your battery fully charged? As above, check pin 86 of the relay base to see if you have 12v.

In regard to the handbrake, does the instrument panel bulb come on when you engage the handbrake?

Cheers,

Allan

 

Hi Allen,

Just checked pin 86 and I do have 12 volt. Also the parking brake light is up on the dash.

Could this be the ECU? I get nothing from jumping the relay either....

Many thanks!

 

Ed,

You also should have 12v on pin 87. Just to be sure, did you jump pins 30 and 87 on the relay base? If you have 12v on pin 87 and jumping didn't work then the problem could be:

A) In the wiring from the relay to the motor. Check the little 2 wire spade connectors by the motor. Check earth connections are clean and secure.

B)The motor/pump is faulty.

Cheers,

Allan

 

This should help

Link http://www.captainjaguarscathouse.co...ec%20Guide.pdf

 

just imagine it is a hard roof, haha im kidding

 

Thank, Allan.
I will look try your suggestions at my next opportunity.
I'm having another issue, as well. If you could look at it, that would be great.

 

I have a similar problem. The top stopped working on my '94 a month age. Today the top suddenly worked but the rear windows went down and now won't work, sop still works.

Any ideas?

 

Turned out this was my problem. Topped up the fluid and voila!

Your problem definitely sounds electrical. Can't recommend highly enough to download the electrical guide posted above. Don't try to diagnose electronics without it.

Otherwise, follow Allan's suggestions. His advice is excellent.

 

Quite a lot of devices in play just to raise and lower a roof and raise and lower quarter panel windows. I simply refused to put up with all that so I unplugged the roof module and ran wires from the console switches to the relays. I can now operate the roof and windows whenever I wish. No park brake needs to be on or shift lever in park or brake to be pressed. And best of all no little electronic gadget will fail at the most inconvenient time such as when it starts to rain and the roof is down.
Cheers, RagJag

 

RagJag,
My top/windows are working fine but the instant I even think that I am having trouble, other than low fluid, I will rewire just as you did. Smart move.
Jomo

 

Today the top and rear windows started working again. Any ideas why it would start working again by itself (I'll tell my wife I fixed it)