240 bulb failure warning unit

hey all

have a 245 1987
my bulb failure warning unit burned through yesterday
the parklight on the right and left tail side won't work anymore

how is it possible to burn through?
can this happen once in a while?
or is this because of the high age?
or is there somewhere something wrong with my elec. system??

what does this thing cost new?
or can i use a used one?

tia for the help

kwijlebabulus

 

The usual cause is cracked solder joints on the circuit boards inside. The
cover pops off the unit fairly easily, it's a red can located up under the
dash, unplug it, pop it open, and inside there's several stacked circuit
boards. It should be pretty apparent looking at the solder joints which ones
are cracked and dull looking. You can buy a new one but it's pretty
expensive and not very hard to fix the old one.

 

thx james

i looked inside => the unit melted down at 2 or three points, so it's almost
impossible to fix it , unless i put in a whole new piece in it

but i still wonder how this can happen!
perhaps the 3rd brake light?
i also replaced the 2 tail foglights by a 5/21Watt bulb
the 21W are for the fog
the 5 W are connected to the standard tail parklights
but it would be very bizare when the unit burns because of 2* 5W

the car has a hook for a trailer, so it can't be the extra 'connections' neither
from the trailer plug or the two 5W bulbs

or can it just be the age of the unit?
perhaps a bad contact in it?
...........

tia

kwijlebabulus

 

my 88 did the same thing with the left taillight,I didn't know about the bulb
failure relay til i saw one on ebay,all I knew was that i wasn't getting power
to that side and i needed my inspection that day to beat the new emisions
deadline here,so as a temporary fix I spliced into the wires going to the right
taillight and ran power over to the left,the bulb warning light is on,but my
lights work. mark

 

hi alex

i have several bulbwarningrelais lying around and live only about 3
miles from you
so don't hesitate,i will even help to solve you electrical problems


marc

4*960
1*740 16v
1*tatra 613-4