screeching sound like fan is catching

[MadeInJapan]

Like I've said before, I believe that there is a positive short to the wire that engages my starter- that's why it starts in every gear- the 12V to the starter is by-passing the PNP...at least this is what I took away from my just now dangerous experiment.
Okay guys- good night...talk to you tomorrow. I can live with this for now...I have to.
-Dave

[BEJinFbk]

The PNP switch does a number of things. It has something like 15 contacts.

It's the starter safety switch that only lets you crank in Park or Neutral.
It activates the back-up lights, and there's 12 volts present at those
contacts when the key is on.
It tells the TCM what gear the shifter has put the car in.
Heck, it's even tied into the cruise control.

My point is, if the PNP has problems, it could be the culprit here.
Could be broken, corroded, who knows? Certainly worth having a look at.

To me, the strange thing here is that the starter solenoid is latching up.
The only thing that comes to me is that something is putting a residual voltage,
lower than the 12 volts needed to initially engage the starter, but high enough to
keep it engaged once it is. The PNP is the first place that I'd look for something
to go wrong that could cause that to happen. ( A moving part that wears ).

Here's another question/experiment for you -
Key on in the run position, motor off, green wire unplugged from the starter:
what's the reading at the green wire's connector? Any voltage? There shouldn't be.

[BEJinFbk]

And even though it sounds like you found the right relay,
you need to know that 85, 86, 30, 87 and 87A are found
on relays all over the world. It's part of the DIN standard.
You'll find the same numbers on all of your 4 and 5 pin
general purpose relays and many more out there.

More here for anyone that cares:
http://en.wikipedia.org/wiki/DIN_72552
http://www.the12volt.com/relays/relays.asp

[cn90]

...Here's another question/experiment for you -
Key on in the run position, motor off, green wire unplugged from the starter:
what's the reading at the green wire's connector? Any voltage? There shouldn't be.

1+,

First, d/c the green wire from starter and measure Voltage (not Ohms) between ground and the tip of green wire.
The factory design is:

Report back what green wire voltage (not Ohms):
- Position I: should be 0V
- Position II: should be 0V
- Position III: should be 12V

I suspect the green wire @ Position II ---> 12V! Which causes this saga.

Anyhow, trouble-shooting electric problems requires:
- Good understanding of electrical circuit
- Difference between Volts and Ohms.
- Proper use of Multimeter
- Good understanding of the engineers' design of the car
- Good understanding of relays
- Good understanding of connector: easy to get confused... A good trick is to hold the relay up and with a piece of paper map the corresponding sockets terminals. Always refer to the piece of paper, so instead of looking at the socket, you look at your diagram on the paper.

[jimmy57]

My suspicion is battery acid in the gear position sensor wiring.
The current needed to pull in the starter solenoid is 4 amps but once engaged the hold in current is .5 or less. That lesser amount of current can be conducted by ACID bleedover.
Uses your voltmeter and go between ground and then probe around the gear position sensor (PNP as everyone calls it here) connector on top of the trans.
Did the battery slide over, more to the point, did it tip over when you hit the bump?
The connector is accessed below the air cleaner assembly.

I have been busy and the brief times I visited here I saw this post and figured it was about a blower motor squeal. I looked this morning because I saw the count and wondered how serious of a screeching blower problem could this be.

[cn90]

MadeinJapan,

Do a quick test for me.

- Leave key OUT of ignition. Put everything back (green wire connected to Starter, Starter RELAY back in place).

- Open the upper fusebox near the driver windshield glass. This is the place for Cruise Control Relay Module, Fuel Relay etc.

- Turn key to position II, your starter will run (as you said earlier). Pull the Cruise Control Relay Module, does the starter stop running now?

Volvorelays.JPG (77.3 KiB) Viewed 1072 times

[cn90]

...The fuse that controls the IAC, MAF, the Injectors and the Control Module Power Supply keeps blowing too. It's somewhere in this circuit but I can't figure it out...

Look at the diagram below, EXACTLY which fuse blew when this whole saga happened?

VolvoRelay.JPG (58.51 KiB) Viewed 1185 times

[BEJinFbk]

MadeinJapan,

Do a quick test for me.

- Leave key OUT of ignition. Put everything back (green wire connected to Starter, Starter RELAY back in place).

- Open the upper fusebox near the driver windshield glass. This is the place for Cruise Control Relay Module, Fuel Relay etc.

- Turn key to position II, your starter will run (as you said earlier). Pull the Cruise Control Relay Module, does the starter stop running now?

To clarify -
As I understand this problem, the starter only
overruns AFTER it has been initially engaged.

[cn90]

...My point is, if the PNP has problems, it could be the culprit here.
Could be broken, corroded, who knows?...

Like I've said before, I believe that there is a positive short to the wire that engages my starter- that's why it starts in every gear- the 12V to the starter is by-passing the PNP...

I am thinking BEJinFbk may be right, something going on in the PNP Switch.
Tons of DIYs on how to remove it and clean it (in forum).

But this is bizarre because the PNP switch is only powered when the key is in Position III.
Does anyone have an electrical diagram (a detailed one) for the PNP?


This thread deserves to be called" Thread of the Year"!!!
MadeinJapan....don't jump into the lake yet lol.

[cn90]

...To clarify -
As I understand this problem, the starter only
overruns AFTER it has been initially engaged.

I re-read MadeinJapan's posts, I think you are right.
It is kind of confusing because it was all over the place lol.