Reference: 1993 240 Sedan Brake Light Problem Fixed (new sensor worked)

This is just for reference as I just struggled through this problem and
found many posts helpful but couldn't reply because they are older
threads. But I wanted to post the resolution for reference for someone
else.

Problem: 1993 Volvo 240 Sedan with all lights working except brake
lights (including third brake light in back window). Fuses ok (changed
twice). Bulbs ok (tried many). Power through brake switch (the one way
up above the switch for the cruise control). Had checked power to back
flexible circuit board and power to the white plastic connectors was
coming in only to parking, flashers, and fog lights. So it seemed the
board was OK with the problem between the pedal switch and the
connector in the back (sedan).

Pulled off the hard plastic near your knees (pull out plastic tabs and
remove to star screws and then bring down and out). Reached up and
pulled the black and red bulb failure sensor (~ 3 inches long and ~
1.5 inces diameter) down from the clip that holds it. It comes apart
(the black and red part but it was difficult.

As others posted, tested lead #54 by slipping in the voltage meter
probe. Getting voltage in on #54 meant (I think) that power was coming
in from the brake switch when the pedal was pressed. That is how I
ruled out the brake pedal switch - it was easier to get to the senor
then the switch. So then I kept the pedal down and checked the two
out-going leads (#54L and #54R) and there was nothing on the meter.

I replaced the sensor with a $127 (late on a Saturday - no time for
price checking) one from the volvo dealer and it all worked!

Hope this helps....

 

thanks aplenty! my '90 245 has it's brake lights on all of the time. was
this your problem also... why can't i just do a simple switch from the
pedal to the brake lights... i've ignored the problem for 2 monhts...
used to be a simple replacement on my previous 122 and '86 240s...

am i missing something?

thanks for any advice!

js

--

wrote:
: This is just for reference as I just struggled through this problem and
: found many posts helpful but couldn't reply because they are older
: threads. But I wanted to post the resolution for reference for someone
: else.

: Problem: 1993 Volvo 240 Sedan with all lights working except brake
: lights (including third brake light in back window). Fuses ok (changed
: twice). Bulbs ok (tried many). Power through brake switch (the one way
: up above the switch for the cruise control). Had checked power to back
: flexible circuit board and power to the white plastic connectors was
: coming in only to parking, flashers, and fog lights. So it seemed the
: board was OK with the problem between the pedal switch and the
: connector in the back (sedan).

: Pulled off the hard plastic near your knees (pull out plastic tabs and
: remove to star screws and then bring down and out). Reached up and
: pulled the black and red bulb failure sensor (~ 3 inches long and ~
: 1.5 inces diameter) down from the clip that holds it. It comes apart
: (the black and red part but it was difficult.

: As others posted, tested lead #54 by slipping in the voltage meter
: probe. Getting voltage in on #54 meant (I think) that power was coming
: in from the brake switch when the pedal was pressed. That is how I
: ruled out the brake pedal switch - it was easier to get to the senor
: then the switch. So then I kept the pedal down and checked the two
: out-going leads (#54L and #54R) and there was nothing on the meter.

: I replaced the sensor with a $127 (late on a Saturday - no time for
: price checking) one from the volvo dealer and it all worked!

: Hope this helps....


--

 

It's a reasonably common problem, the solder joints in the sensor crack,
takes about 10 minutes with a soldering iron to repair them.

 

That sounds like the switch has failed.

 

I thought about soldering (as other posts had mentioned) but had run
out of energy and patience for the day. But you are right - $100+ part
versus $1.00 of solder...should have been a simple choice... :/

As a side note for the other post, my problem was that the brake lights
would NOT go on. It was not the case that they stayed on all the time
as I saw in other posts. AS James wrote, that does sound more like a
switch that is stuck on.

Remember, at least on my car with cruise control, I think the switch
for the brake lights is higher up and a little harder to see. The first
one I see underneath is for the cruise control (it has a t-connector
for the vacuum hose and then a small two-wire plastic connector).

When I first checked things, I checked voltage on both sides of that
switch - which only meant power for the cruise was working. I really
hadn't ruled out the brake light switch like I should have until I
checked voltage coming in to the senor.