electrical fault behind the dash !

[clarkie]

as most will know iv stripped my interior out and started from scrath, i posted up a few weeks ago moaning that my horn doesnt work and now i think the problem could be more serious than i first thought! my fuel guage tells me my tank is empty when i fill it up and goes to a different position every time i turn on the ignition and never gives a true reading so im having to reset the milometer every time i fill up and watch the miles... i fitted a second hand fuel pump and sender into the tank and its made no difference so i dont think it was ever that in the first place...

now my horn has stopped working so i removed the actual horn from behind the bumper and tested it on the battery and it works fine! i connected back to the horn and nothing! it is an aftermarket steering wheel with a single centre horn, the contacts seem to be fine as does all the wiring around the shroud as it was working fine for the past 18 months but suddenly just stopped one day. i am increasingly getting a bad feeling i have maybe trapped a wire behind the dash or bridged a wire by mistake or something to cause these 2 problems i dont want a massive bill for getting it checked out so i just wondered if anyone else could shed light on the situation.

my next step i think will be to get a voltmeter and see if the live to the horn is actually producing a current so then at least ill know if there is a break in the feed somewhere along the loom but as for the fuel guage its a strange one... its not the clocks as i borrowed the clocks out of my sisters fiesta and it gave the same readings on hers so it cant be faulty dials...

im at an end with this now i really need to sort it as it a niggly problem that just keeps haunting me!

 

[Anonymous]

Clarkie....

Not sure what help you want here... but I would do the following:

Bit obvious, but check fuse.
Locate live at steering wheel, volt test this to a ground point (asuming it will be premanent live, with ignition on?).
Do continuity test across steering wheel/horn contacts. Press horn button, multi-meter should beep/buzz.
At steering wheel, locate the live wire to horn. Continuity test between this end and horn end (get long length of wire, join one end at horn end and test between other end and horn live). Or if everything checks ok, do voltage test at horn end with steering wheel button pushed.
Check/clean horn grounding point.

Hopefully this should locate a cabling faul, if one exists....

Not sure if this is the sort of help you need, or whether it will really be this easy, but just throwing some ideas around!

 

[clarkie]

cheers for reply mate i have checked all fuses and checked the contacts for ground points and cleaned them up etc... i do not have any volt equiptment or anything like that so im going to invest in some and check as you say... otherwise its dash out and do some proper digging.. i fear when i fitted my new dash i may have trapped the loom somewhere and caused these faults

 

[Anonymous]

Just a cheap, simple volt-meter will do what you need. At least if you do find a 'suspect' wire, you may be able to trace it through and sort it out without pulling the whole lot out.

Good luck! k:

 

[warrenpenalver]

sounds like a short somewhere or an earth problem. the dash goes bananas when you have low voltage such as electrical faults.

 

[martinthrapston]

if in doubt run another wire from the switch to the horn k: