1982 xj6 series 3, This may be a silly question but im just not sure. I was testing all the fuses today with a 12v test light and I was getting power but some I wasn't. I wasn't getting power from the direction indicator fuse but the signal and light work fine. Do some fuses not get power until the car is actually running? I remember I wasn't getting power from fog lamps, panel illumination, front parking lamps, air conditioning/heater motors, door lock relay r.h dip, r.h main, l.h dip, and l.h main. I also was trying to fix my horn, when I push the horn on the wheel I hear a noise from the hood like its working just not making the sound don't know where the sound is exactly at though, any ideas?

 

Yes, some fuses are 'hot' only with the key "on", or when the particular circuit is switched on.

This should help with fixing the horn

Horn Circuit Checklist

And, if you need to replace any fuses you'll need this

Fuse Conversion Chart

Remember to clean the fuse clips while you're in there. If the clips are corroded the power might not get to the fuse

Cheers
DD

 

Thanks Doug, I remember a couple threads back you were explaining how to examine the heater valve and have a helper turn the knob. Can you explain this again to me? Do you have a checklist for diagnosing the cruise control? Mine only accelerates faster and faster when activated. Is it true that a fault in the cruise control system can mess with the brake system?

 

It is wise to install a battery cable disconnect.
Good for ending battery drain, theft and preventing fires.

 

The valve has an external actuator arm. When a helper turns the control knob from hot to cold, or vice versa, you should be able to see the arm move

Not a checklist exactly, but good info
Cruise Control


Maybe on newer cars with smart cruise control but on our old Jags there is no tie-in between the two systems

Cheers
DD

 

if you can hear sort of a drowned horn sound, then it is the horns that may be bad.

the fuse for the Horns is located above and behind the battery in a separate fuse holder with Brown wires.

each horn (Low/High pitch), has an adjustment screw on top that can help to free a stuck diaphragm inside the horn.

with ignition switch ON, have someone press the horn as you unscrew the adjustment screw then tightening it until you get a blast from the horn, it might revive the horns.

the horns are located under the front bumper at the center.

 

Ahunt4:


A sharp smack with a rubber mallet can awaken sleeping horns. I have mine disconnected at present. The power supply is a big brown wire that crossed behind the battery. there is aplastic case there as well with an infamous glass fuse.


The ignition on supply from the switch is green. The relay is triggered by a black wire from the horn button. There is a brass shoe on the column that completes the circuit while allowing the shaft to turn.


Note, the key must be on for the horns to sound !


Giovanni:


With all due respect, tat switch gives me a couple of concerns and a question. An answer might resolve at least one concern.


1. That frayed cable clamped in to the switch. One of those "bodges" caused me a lot of issues with a flat spot in a past turbo'd Corvair, sorta Corsa project.


2. Is the knob robust enough to handle large current draw as in starting?


3. What is the black box.


4. How about memory storage as in ECU's and radios?


Perhaps the answer to 3 resolves four.


Bur, in turn raise the issue that the battery isn't disconnected in total at all?


Carl

 

Do you guys have a pic of the fuse and wire to the horn that sits behind the battery? For some reason I don't see anything back there

 

seen on the lower left corner of picture, over the battery