1997 850 NA Automatic not starting

BlackThunder · Post by **BlackThunder** » 06 Oct 2018, 19:26

I was able to see voltage going to my starter and was able to jump the starter and it engaged. Ignition switch was replaced last Spring, new battery last year and a new, used Cam position sensor was just installed since the car had problems starting all the time. Sometimes it wouldn't click or anything so I figured it was the cam position sensor.

Anyway, with all of that I am still not getting the car to start. I am down to thinking it is the PNP switch. No error codes were shown before all of this non-starting began.

What do you think? Should I attempt the PNP switch clean/repair?

Post by **erikv11** » 06 Oct 2018, 20:20

How about is the voltage good thru the positive cable? This is a really common problem, the cable pulls away from the cable end, under the insulation, and corrodes away. Looks fine but hardly works. Check if the wire at the red cable end gets warm/hot after running for a while - that would indicate poor conductivity there (high resistance).

Did you already pull both battery cables and clean them where they contact with the battery posts?

If you suspect PNP issues, push the button and row the shifter through the whole range about 20 times back and forth, see if that makes any difference.

smoggyama · Post by **smoggyama** » 06 Oct 2018, 20:58

I had the same problem with my '96 850 T wagon. The OBD2 code indicated cam position sensor CIRCUIT. There is a 5 volt regulator on fan shroud/driver's side with 4 leads to the harness. Check those connections. Drive cheerfully. P.S. I just got a strut tower cross bar ($100) and it makes a tremendous improvement. And change your break and trans fluid.

Post by **abscate** » 07 Oct 2018, 06:13

BlackThunder wrote: ↑06 Oct 2018, 19:26 I was able to see voltage going to my starter and was able to jump the starter and it engaged. Ignition switch was replaced last Spring, new battery last year and a new, used Cam position sensor was just installed since the car had problems starting all the time. Sometimes it wouldn't click or anything so I figured it was the cam position sensor.

Anyway, with all of that I am still not getting the car to start. I am down to thinking it is the PNP switch. No error codes were shown before all of this non-starting began.

What do you think? Should I attempt the PNP switch clean/repair?

Is it dead, cranking well, no firing, cranking so-so, cranking amd sputtering?

BlackThunder · Post by **BlackThunder** » 07 Oct 2018, 07:39

Full charge on the battery, no cranking or clicking whatsoever. But I was able to jump the starter. There is a small break at the red lead from the battery but it seems to be conducting. I'm new to using the multimeter - how would I check/know that was going bad?

Should I put the old Cam position sensor back on and see if that makes it fire?

@smoggyama I have a strut tower brace too - that and the poly inserts made a surprising improvement.

dj_v70 · Post by **dj_v70** » 07 Oct 2018, 10:35

If your car doesn’t crank/click, cam sensor has nothing to do with that.

What do you jump to get your car to crank? Smaller post on the starter? Where are you jumping from? Battery positive post within same car? Answering these questions will narrow down troubleshooting.

Post by **erikv11** » 07 Oct 2018, 14:26

BlackThunder wrote: ↑07 Oct 2018, 07:39 There is a small break at the red lead from the battery ...

I'm not really understanding you ("jump the starter") but anyway, this red lead is often the problem. When you start it after jumping, does the cable get warm? See above.

BlackThunder · Post by **BlackThunder** » 08 Oct 2018, 17:52

I was able to take the green wire off the starter and attach a cable from the positive terminal of the battery to where the green wire connects and it moved the starter. I couldn't tell if the red wire from the battery was warm or not. There did look to be some corrosion on the green wire connecter- inside the connector. I cleaned the post it connects to.

: Green wire connection with corrosion

I did the moving through the gears vigurously (20 times) and that didn't seem to change anything either.

Dustin

dj_v70 · Post by **dj_v70** » 08 Oct 2018, 19:44

Dustin,

Ok, that helps. Obviously, your battery and starter are good. We need to to check out all wiring to the starter solenoid. This is the green wire that you mentioned.

Please note that your wiring diagram and component locations can be found for your vehicle at volvowiringdiagrams.com

I am looking at page 28 of TP3917201. This is power supply and starting for 1997 850 diesel. I am making the assumption that diesel starting electrical is close enough to your even though your car is not a diesel. Looking at some diagrams for other years, this seems to be a safe assumption.

Your power for starter solenoid starts at battery, goes through your ignition switch, through alarm relay and then through your pnp and then to starter. I’d recommend starting troubleshooting at alarm relay since it is easily accessible.

You mentioned that you don’t feel comfortable with a voltmeter yet. So, first step is to make sure you are using it correctly. Set your voltmeter to DC volts. Some meters offer multiple dc voltages. Choose voltage that is closest to, but higher than 12volts. Next place black meter wire on negative battery terminal and red meter wire on positive battery terminal. Make sure you read something like 12.6volts. Is so, you are setup to use your voltmeter!

For most (all that I mention) voltmeter measurements, black meter probe should be on negative terminal of battery. Remove alarm relay (see Volvo diagrams that I referenced above for relay location). Put red meter lead in relay socket position marked 50. Have helper turn key to try and start engine. Do you see 12volts on your meter? If so, wiring is good to this point. If not, wiring issue is before this, possibly ignition switch issue.

When you jump the starter as you described, does the car crank normally? What I mean is, does it crank slowly like your battery needs charged? If this wiring is only problem and the problem isn’t the ignition switch, car should start if ignition is in run position while you are jumping car. Does it start?

Please answer questions directly above and take above measurement on relay and report back, we can try to finish troubleshooting this with you.

Post by **erikv11** » 08 Oct 2018, 23:15

BlackThunder wrote: ↑08 Oct 2018, 17:52 ... I couldn't tell if the red wire from the battery was warm or not. ...

Feel it before you start the car, drive it around for 20 minutes, check it again. If the red cable end is bad then the wire and/or nearby cable end will be hot, almost (or even) hot enough to burn you so be careful.

This check doesn't supersede dj_v70's good advice, just explaining how to complete this good diagnostic test.