Hi Spooky Jay. Been down the starter problem road for one reason or another a number of times in the past year with my '95 940s. I'm finding it interesting that you didn't mention having some kind of intermittent starter problems, as is so often the case. Has wiggling the shifter ever made a difference? -if so, of course suspect the neutral safety switch. Has turning the key back and forth a number of times ever made a difference? -if so and the starter solenoid has been heard clicking then it’s possibly a dead spot on the starter motor, if the starter solenoid has not been heard clicking then it could be a bad ignition switch or a sticky solenoid. Has turning the key extra hard sometimes been needed? -if so, then a worn ignition switch.

To add to the advice you've already been given, I'd begin my diagnosis at the open remote starter switch connector (pink wire) located at the driver's side fender. The NSS lives in circuit between it and the starter solenoid terminal (blue-green wire) on the starter. The ignition switch lives between it and battery +12V. This makes it a good diagnostic point as well as a useful remote start location, plus you don't have to start by getting your hands dirty or taking things apart.

I'm sure you already know a lot of this, but in my usual style I'll go into detail for the sake of others later finding this thread and to perhaps offer a few extra tips for you along the way based on my experience.

1) Momentarily apply 12 volts to the remote starter connector -it's not high current, so don't worry about needing extra heavy gauge wire to connect to the battery.

If the starter now kicks into action (or at least now clicks and didn't before) then the problem is almost certainly the ignition switch. You can confirm that by holding the key in the crank position (KP-III) and see if you get +12V at that remote starter connector, if not then that confirms a bad switch. Worn ignition switches usually start misbehaving with intermittent problems, such as having to wiggle the key, turn it extra hard to operate the starter or having the lights blink or the engine cough/die while running when you wiggle the key. I had one go like that recently and had to replace it -premature wear possibly due to often heavier multi-key chains. Rather than working blind from below, best done from above removing the instrument cluster for easy access to that otherwise miserably buried top screw -have a light and mirror handy to more easily see what you're doing. The aftermarket switch I got looks exactly like the genuine Volvo except for the markings.

Now if nothing happens when you apply 12 volts at the remote start connector then it's now likely either the NSS or the starter motor/solenoid.

2) Fastest way to diagnose the starter is to do as is normally suggested, just short the red +12V battery terminal on the starter to the starter solenoid terminal next to it using a screwdriver, jumper wire or whatever. This requires bending over and getting my hands dirty, possibly putting a pit mark in a screwdriver making it look like I slipped again in an electrical breaker panel, so that's why I often prefer to delay this simple test. If still nothing happens then don't forget to verify that 12V is indeed getting to the starter before declaring it a bad starter. Starter problems often begin intermittently with either a sticky solenoid or a dead spot on the starter windings. Solidly tapping a few times on the starter solenoid and/or motor casing with a stout rod, solid stick or hammer will often jar things enough to allow cranking, further confirming where the problem is. I often start packing a length of 2x2 as well as making sure my jumper cables are handy at the first hint of failing to crank properly. The top starter nut is a bit of a bear to get at and loosen, needing good access for leverage from below and above, so best done on a hoist. This is one occasion when I was more than happy to let a mechanic do it and put in a used one from their yard. Volvo starters are pretty reliable, so I have no problem going with a decent looking used one rather than having mine rebuilt at a local starter/alternator shop or ordering in a reman starter.

3) To better diagnose the NSS, connect an ohmmeter between the remote starter connection (pink wire) and the starter solenoid terminal (blue-green wire) with the meter visible from inside the car. Move the shift selector in and out of the Park position to see if you're getting continuity. Wiggle the shifter in the park position to see if it's intermittent. Remove and replace or open/clean the NSS as needed. The NSS is indeed a bit of a nuisance job, but at least there's minimal time required on your back under the car in bad weather. As you may well know, the NSS is mounted using star-lock push clip washers on two long and mildly breakable plastic studs. By working carefully, I've always been able to get the clips off without breaking the studs. I start by notably bending up two or three of the little tabs in the middle using a sharp pointed awl. It's then easy to lift up one edge and carefully keep working around under the clip with a tiny screwdriver or pointy tool to twist it up and off the plastic stud. I don't care if I break the little tabs in the middle of the clip when I bend them up as I'm not going to re-use them. I prefer to use a common acorn nut (bulk fastener bins at many hardware stores), 5/32" or 3/16", I can't remember. I just let it self tap onto the plastic stud using a nut driver to hold it square, gently snugging it up enough to solidly hold the switch so as not to strip the plastic. Next time, and there will be a next time, it won't be so fiddly.

Also, while you've got the NSS out, it's a great opportunity to replace any dead bulb or replace that all too often broken black plastic shift indicator blind (p/n 3549927, available from FCPEuro and others, don't loose the little square white insert!!). If you break a plastic stud, drill a small pilot hole in the plastic shifter housing and use a long sheet metal screw, grinding the tip down a bit if needed.

BTW, speaking about the NSS and shifter assemblies, for the later 940 shifter assemblies with the sometimes trouble prone shift lock solenoid and microswitch where you can't get the lever out of Park, the microswitch on the other side of the shifter assembly is similarly mounted on even thinner plastic studs with a (single) star-lock clip. One of mine actually worked its way loose on its own and started giving trouble, to the point the switch got bent up -fortunately I was able to successfully straighten it. I likewise use acorn nuts on those plastic studs -1/8" as I recall. On another occasion I found a broken plastic pin for the microswitch, replacing it with a long, thin screw and another occasion I lost or broke the clip and, not having an acorn nut handy I just melted the ends of the pins to hold the switch in place. [I'm currently fighting for the third time with a troublesome shift lock solenoid in one of our 940s, just about ready to bypass it completely -grrr.]

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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now