i have an actual hard copy of the 1992 740/940 greenbook wiring diagrams.

this 10 pin connector shown on some other pages as 'connector at central console', and the arrow points to somewhere behind the cigar lighter. in addition to the seat heaters, the right front parking light, rear ashtray light, seat belt reminder lights, drivers seat belt latch sensor, and the parking brake switch all go through it.

 

Today I had a new Kenwood stereo installed, of course they cocked it up !Driver side works fine both doors , passenger front sounds weak ( I suspect they wired it out of phase)rear pass. door doesn't work at all , and neither dash speakers works ! BTW , now the door chime and seatbelt light don't work ! They tell me I need new speakers on pass. side and dash (they say these are blown out) I told therm I would be back early tomorrow ready for them to fix this mess. (When I got the car , was no radio at all installed , P O said was stolen) So I have no real way to tell whats right & wrong. On the off chance I do need new speakers what size will fit? how about putting tweeters in the dash? Please give me some ammunition for tomorrow ! Thanks !

 

you're better off disconnecting the dash speakers and putting 5.25" or 6" 2-way coaxial in the front doors. the factory dash speakers on the 740/940 are custom, the rectangular grill is part of the speaker casting, they are about 3.5" and only so-so when they were new. 5.25" will fit best in the doors if you use an adapter like...
PVC Speaker Adapters - CNC Machined - In Stock or Custom Made
(a stereo installer will probably make something like this out of paperboard or masonite and charge you $100 more).

see this link for my 6" install, using the /very/ nice sounding JL Audio C2-600's ($109 on ebay, $180 list at the local rippoff store)... this requires you modify the speakers by trimming off the flange on one side so the factory grills will fit over them
https://volvoforums.com/forum/volvo-...71/#post325719

I'm betting they botched the wiring. especially if they messed up door/seatbelt chime.

I always do my own stereo installs, I dont trust those installers.

 

ok , Im convinced, won't bother with the dash speakers for now,,,are the front and back door speakers the same size? I am thinking I may be able to get them to remove the driver side rear (which works well) and put it into the pass. front door area. if that works , I will buy a pair and have them mounted in both rear doors. any idea what they botched up to screw up the chime?

 

I'd put the good speakers in the front doors. I put 6" in front and 5.25" in rear, and it sounds very very good. if I have rear seat passengers, I usually turn the backs down a bit so we can talk. I used JL Audio C2-525X in the back (5.25" coaxial, with those adapters I linked, which made the install trivial, just remove the door panel and screw in the adapter and screw in the speakers, then plug them into the factory wires. with those specific speakers, I had to open up the metal hole where the magnet goes in the door a bit, using a dremel with a cylinder grinding stone, this was pretty easy, just take off a hair at a time til they fit easily. do mount the speakers with the wires on TOP, as they'll fit better when you install the door panel on the doors.

 

Stereo is in and working well(didn't fiddle w/dash speakers). Door/seatbelt chime is working. WHEW ! I think next is the o2 sensor, maybe next week. Then the fuel guage , THEN the front suspension bushings and maybe shocks all around . At that point , I can look forward to many carefree years of driving with no problems what so ever ,,,,right? right?? btw , I am getting around 20 mpg , is that about right?

 

I just went out and disconnected the elec. plug to the fuel sender , danced naked under the moon light , scattered some chicken entrails, and plugged it back in and ,,,,, fuel gauge now works !

 

how was the wire off that sender? if the wire is crappy, odds are it comes back.

 

no clue , but none of the wiring looks damaged , connector is dry

 

just went out and re-started tyhe car , still working. At least now I know that the gauge and sender work ! at most , what , new connector?

 

looking on amazon can you give me a part # that I should be looking at ? Will any off brand work as well? do I need Bosch ? I really wnat this to be Plug-and-play !

 

it was probably just some corrosion or whatever and simply reseating it did the trick. It also could be the wiring that goes through the plate into the tank, thats a known weak spot on some of these cars, especially 240s, unplugging and replugging could have jostled it enough that its conducting OK for now.

 

Darn you Pierce , and your "experience" stuff ! Went for a ride today ,,, no gas gauge !! But do I now know that the gauge and sender are ok , just a wiring bug-a-boo ? Can you tell me what to look for on that front? I was REALLY hoping that cleaning the contacts had fixed it ! I know that the fuel pump works off the 4 ? wire plug , is the gauge on that circuit also ? whats the mysterious black box mounted next to it ?

 

this is a 940? the fuel level sender and in-tank fuel pump are assembled together and in the gas tank, which is accessed from behind the back seat... if its a wagon, you fold the back seat down, and lift up the plate that is immediately behind the seat, I think its the left rear seat, there's two(?) screws and that plate comes off entirely... on a sedan, go into the trunk, and remove the carpet and left wheel well inner liner. under the plate or carpet there's an access panel (a few more screws), and the top of the gas tank is exposed. it has a big plastic lock ring that has a clamp around it...

the brown (pin 3) and grey-white (pin 2) wires are the fuel level sender, its a variable resistance (not sure of the values), the purple (pin 1) and black (pin 4) wires are the in-tank fuel pump, yeah, all on the same 4 pin connector in the luggage area.

To take the sender/pump assembly out, you loosen that clamp then unscrew the plastic lock ring (leave the clamp around it!!) and once its off, re-tighten the clamp til you reassemble things (that ring has a nasty habit of not wanting to stay on the threads if you dont leave the clamp tight on it until you're ready to reassemble). there's two gas hoses, I think a tank vent hose, and the connectors for the fuel pump and tank sender, you disconnect all this before you remove that ring. once the ring is removed, you can then carefully remove the plate with the fuel pump and sender assembly... its tricky, you have to kind of lift, rotate, twist, lift some more, rotate some more to extract it as there are baffles inside the tank that get in the way of just pulling it straight out. you'll need to repeat that sequence backwards to reinstall it, more fun! oh, replace the washer that seals the flange onto the tank, too.

once you remove it, you can repair the wiring and/or sender. frankly, I'd replace the tank pump, hose, and fuel intake sock and any wiring thats not totally perfect as the effort to get it out is not something you want to repeat.

here ya go!
Volvo Fuel Tank Pump/Sender Replacement

 

wow , just,,,wow !

 

Ok , this sensor business is outta hand ! these things are expensive ! Can you tell me how/if I can just do away with it , and get the engine light off? How will doing so affect the engine performance/fuel economy?

 

'the engine light' ? Do you mean the Check Engine light? you read the error code(s), and troubleshoot whatever problem is indicated, hopefully finding the root cause and repair it.

fixing the root cause should result in optimal engine performance and fuel economy. leaving something broken and ignoring the error, well, the effects of that depend on what the root problem actually is.

 

I decided to bite the bullet on that O2 sensor , ordered one on line should be here by the time I get the volvo back from the shop. ( new front bushings tie rods ball joints etc) also having the fuel sender replace or repaired , along w/new flame trap as I think that may be the cause of the NEW oil leak (pressure build up?) I need this car to be steady as a rock by winter ! I did the seafoam trick in the gas tank , and I believe it made a difference on initial acceleration. Do I want to put some in the engine oil to clean the other side? So far the car has been a great daily driver and I really enjoy it.(when it's been just too damn hot for the Miata) Hoping winter weather , assuming we get any , will prove the same !

 

Brought the 940 home w/new tie rods,sway bar ends , and ball joints , and assorted bushings ,really drives like a new (old) car ! The fuel sender proves too expensive a fix for me right now $780.00 !! Also replaced the flame trap and attendant hoses , new oil leak fixed ! Thanks to you guys for that tip. Hope to install the new O2 sensor this weekend , then maybe air filter , cap , rotor and plugs, and maybe an oil change and trans filter change? Trans was rebuilt about 100,000 miles ago feels fine but better safe , no ? What say you?

 

the fuel sender is something that's quite doable with just some hand tools, and a fair amount of patience.. the part isn't that expensive, shops just charge a lot because it takes a fair amount of futzing around to get it out and back into the tank.

AW70/71 transmissions are good for 250-300,000 miles of HARD driving as long as they get an occasional flush and filter service. so yeah, flush-n-filter. engine oil changes are a 5000 mile thing in my book (which says "Volvo" on the cover )