in my 87 244, the shift up light is always on, even when in 5th gear. also whenever i have my lights on the little blown bulb dash light comes on even though i know all of my exterior lights are working. any suggestions or ideas on whats going on?

 

the shift light is connected to a relay-like control module, this control module takes input from the tachometer, speedometer, and a switch on the clutch pedal, it lights when it thinks the RPMs are too high for the speed. I believe its under the dash to the far left

the bulb failure sensor is a round module that compares the current to the left and right bulbs of each pair. any differences in the current can trigger it. corroded sockets and/or wiring connections, mismatched bulbs can trigger it. You should always use tail light bulbs that have chrome not brass bases, in American car parts stores, these are often on green Sylvania brand 'hang cards' that say OEM. I always replace the left and right bulbs of any given pair together to forestall such issues. This bulb failure sensor is under the dash, left of the steering wheel, mounted horizontally.

 

what do these modules look like? is the bulb one a round red cylinder?

 

Yes that's the bulb out relay

For the bulb out - figure out which bulbs are turning the failure lamp on.

The relay cares about - the 4 rear parking lights - two on each side, commonly the outer bulb holders/housing/circuit board melts/gets a bad connection and cause either brake bulb or parking light connection problems.

It cares about the 3 brake lights, and the low beam headlamps.

So does it come on with parking lights? (all 4 working? ) With brake lights? (all three working?) or with low beam headlamps? If it's on all the time with the lights (and not when braking with the lights off) - it has to be either the headlamps or the rear parking lamps.

For melted brake/parking light problems - move the brake lamp to the rear fog lamp position - the upper inner lens - simply move the brake light wire in the connector at the tail lamps.

As other have mentioned the bulbs must use the same current - so the same brand would be best and the brass base made in china bulbs are usually of poor quality.

For the upshift light - take the bulb out!

 

exactly. not that i've had too many vehicles with a shift light (manual transmission), but i ignored the light in the few that i did drive, and if i owned one, i'd probably disable it to minimize annoyance.

 

https://www.prancingmoose.com/volvor...bfailuresensor

I believe it also compares the left and right front parking lights.

if you turn on just the parking lights, does the bulb out light come on ? then the problem is in the parking lights. if it only comes on with the headligths, then its in the low beams (high beams aren't checked). and if it only comes on when you step on the brakes, then its the 3 brake lights.

upshift relay location (171 on this drawing)
https://www.davebarton.com/pdf/relay_87_240.pdf

and what it looks like,
https://www.ebay.com/itm/Volvo-240-7...-/362968610041

ah this post has the wiring diagram for it. its from a 1985, but AFAIK, a 1988 should be exactly the same.
https://volvoforums.com/forum/volvo-...09/#post461789

 

yeah, my 1989 Jetta GLI had one and it was pretty annoying. that was a short-ratio fast shifting 5 speed mated to a high revving 4-cyl DOHC, and that damn light would have you trying to do 1800 rpm in top gear. the engine was much happier at 3000-4500 rpm than it was under 2500.

 

The only Volvo I've seen that cares about the front parking lights is the 08+ v/xc70. Perhaps the s80 also with the same headlamp assembly. And they are a pain to replace, takes 3 hands. 240/260/740/760/940/960/01-07s60/xc v70/s80 - the front parking bulbs are not part of the bulb out system - but most are still fused left and right - meaning the left front and rear parking bulbs are on the same fuse, but only the wiring for the rear goes to the bulb out relay.

 

ah, thats right, its my 1990s mercedes that monitor the front parking lights. the MBs also monitors the highbeams and even the fog lamps., but they use an electronics module rather than the can full of coils and a magnetic reed switch that Volvo uses.