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Technical Another Wiring Question

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Technical Another Wiring Question

ourden

ourden

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Renewed my horn as it was'nt working, had tested old one first (dud).
New one would not work either:confused: checked relay OK? then put meggar at the two
wires at horn :eek: both live. So question is can I remove centre cover on steering wheel
so I can rewire to horn? as it has an air bag on it.
Or is there an alternative way? (2003 2.8JTD.)

Thanks :)
 
Did you test the wires disconnected from the horn? If you tested with them connected and they both read live this would indicate a broken earth connection.
 
The basic system is similar to the late vans. Test the horn and relay circuits again, only tackle the clockspring wiring as a last resort, or if you are already familiar with the systems. If you are not confident removing the airbag squib, get some help. There are guidelines for doing this. Disconnect battery, removed squib, place face up on the floor, etc. DO NOT test connections with a test light or voltmeter. Remove s/wheel, now you can use an ohmmeter to check the continuity of the clockspring, and check the horn push. It is highly unlikely you will have a problem with these components.
See the post below from 2 weeks or so back, it may help.

Re: Fitting air horns to X250
Horn P005 is permanently earthed at C010. Fused power is supplied to relay contact and winding. The other contact feeds the horn when the relay is activated. The relay is activated by earthing the second winding terminal through the horn push D047. If tested with an ohmmeter when still connected to the horn, both wires will appear earthed as the horn offers little resistance.This is the most common horn wiring system when a relay is used.
On an earlier vehicle with no relay, a fused supply is connected to one horn terminal, the other terminal is earthed when the horn push is activated. In this case both wires on the horn will appear positive if tested with a light or voltmeter. When the horn is activated one terminal becomes negative.
The simplest way to connect after market horns is to disconnect the 2 horn wires, connect them to an after market relay across the windings. Fit a new fused supply to one contact, connect the second contact to the horn, earth the second horn terminal. This means you don't overload the o/e system, don't damage o/e wiring, and if you become attached to your super loud horn system, it is easy to remove it and reconnect the original if you sell the vehicle
Click to expand...
 
After fitting alarm to my van the horn stopped working. Eventually traced to small wire pushing into horn mechanism under steering wheel. Just pushed this connector in slightly and it has worked ever since. Accessible after removing the two cover halves under the steering wheel.
 
Very common fault on older vans, but not on airbag systems as they have a clockspring. The old system used a slipring and contact.
 
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