Boot light always on - help please

[dino]

Hi,

i have a C124 1994. The boot light stays on no matter what. in fact it drained the battery overnight. There are three wires going to the lamp, red , brown and a blue wire attached to the brown.

i've unplugged and removed the boot plunger switch and light still stays on.

if i arm the alarm it the siren goes off.

any ideas? what is the blue wire for - it seems to run to the front of the way somewhere?

thanks, dino

 

[C220GJS]

Your have a constant +ve feed to your boot light through the red wire ,the other side of the circuit -ve earth is made by the brown wire through the plunger switch which makes contact when the boot is open, so your fault must be somewhere in this -ve earthing circuit. You must have a short to earth somewhere on the brown or blue wire (the blue wire is the signal wire to your alarm controller that your boot lid is open).

 

[eric242340]

Take the light bulb out, as a temporary measure, until you fix the problem.

 

[anyweb]

in addition take the switch out and you can actually disassmble it and give it a good cleaning, the switches get 'sticky' overtime and as a result fail to work at all or exhibit strange problems possibly like yours,

if the switch is faulty, the cleaning (with spray oil) may help or you may need to replace it altogether.

cheers
anyweb

 

[C220GJS]

"i've unplugged and removed the boot plunger switch and light still stays on."
Which discounts the switch and why I said the fault must be in the wiring before the switch.

 

[dino]

Sorted!

Result! Thanks for the wiring advice. I had pinched the blue wire in the seat belt anchor point (which i had removed) and that had shorted it.

respect!!!

Dino

 

[anyweb]

well done and good troubleshooting from C220GJS !