I had a look and can’t find the pink wire
service port that you mentioned
Near the round firewall plug in the engine bay
There is only a wire to the brake line connector
A couple of wires or hoses up to the hood

The design incorporates an engine harness
and it plugs into the main harness
at an 8 pin connector
There is an unused 2 wire connector coming out there,
some unused option maybe.

I have a complete harness I pulled from same year sedan
With the same options so I have it laid out
on the floor I’m not seeing differences
Yes I removed a whole harness,
pretty well intact :)


The engine harness is still strapped
to the engine which is nearby
I tried following the starter trigger wire
on that engine to the plug to check continuity
and found none tgat part is a bit hardened

I’ll remove that harness from the engine
to study it or copy it if I need to
It hugs the block so susceptible to heat oil etc



I think I should check if I have 12 V at that 8 pin engine
harness connector on my own car when key is turned

I should check continuity ,
through the engine harness
to the green and blue wire
that triggers the starter.

I can feed the starter from that connector break
to test that section of wire

That 8 pin connector is stuck
, probably corroded and pouring rain out
no garage gave up for the moment. I’ll soak it in cleaner
and try that again tomorrow
that could be the problem area ?

The Volvo schematic I have shows that
wire connects to the ECU
NOT THE KEY!

I did find Hanes and I think Bentley of near
the same years where
the schematic shows that the key switch
feeds the Starter motor , like older cars always did

Since I didn’t find the service port,
and suspect the wire goes to the ECU , I thought
I better not try back feeding anything
might blow the ECU if I’m on the wrong wire or misinterpreting

I checked at the key :
Removed speedometer
Removed 2 screws holding the
ignition switch to the key and pulled the key switch out
Reconnected Speedo wiring

Now I can access the key switch

It unplugs so I tried a different key switch
I can turn it with a screwdriver.

NONE of the contacts at the key switch
are hot with key turned to start ( pos 3)

- this I found surprising, and later
when I discovered that it looks like
there was a wiring change - to the ECU feeding
The starter , not the key ,
I began to figure my schematic is wrong

This is why I want to study my spare
harness to confirm if it runs to ECU

The park - neutral switch on shifter
has continuity when in neutral or park

Those wires run to key terminal
and both showed continuity,
only when in park of neutral

There are two thick red wires ,
fed by the battery to key and
they show 12v no voltage drop
but granted that’s without a load
Still I’m not suspecting bad
battery connections, but possible

I can clean battery terminals and
yes those “extra wires” there on the pos side again
but I don’t see or measure a disconnect there

The engine and starter body are grounded.
12 v to starter terminal DOES make it crank
Problem is not the starter

That’s where I’m at , I’ll continue this as I’m able
Work M-F but I’ll keep at this evenings etc
until I can figure it out

I think I have any spare parts needed.

My spare key switch could have the exact
same issue but it worked before I disassembled that car and was kept dry
I think that probability is low , but possible that they are both bad

I’m suspecting a rotten wire in engine bay side
maybe corrosion got in that 8 pin connector.

Fixing it will be the easy part ,
I suspect .Finding it is probably harder.

I truly appreciate the help !
Phil