No driver in today, so I spent the day cruising around LA doing deliveries in our truck. Great thinking time. This is when I recalled the blue/red wire being from the bulb out relay. Further thought had me remembering how many times I've complemented Volvo on plugs for optional equipment. But I was SO sure those plugs weren't there. Got home and said to myself "if it was prewired, the easiest thing to find would be a plug for the pump. But it's just, it's not, ... .....not....anywhere....except....right here tucked under the brake booster. How about that? Well, if that one is there, the one for the CU must be also." Lo and behold, another half hour and I found it wire-tied to the main bundle of the dash, but tucked down behind the aux instrument area, pushed down beside the ignition switch. All connected up now, no extra wires, no mess. Sometimes we have to let go of the preconceptions to see the light! Thanks for your input and help. Haven't road tested yet, but I'm sure it will be fine barring switch adjustments.

Regards,

DS

Three white 245's, 855, etc etc etc....

Thanks Jessie. Here's what I have:
Control unit is silver, part number 3523537. Eight wire plug plus one female spade. Six wires go from the clear plastic plug and 1 from the spade to the black harness plug as follows:

#1 green /yellow
#2 orange
#3 yellow/ red
#4 blue/yellow
#5 yellow
#6 Black
#7 red/blue
#8 vacant

Same wires exit the other side of the black plug, for which I have the plug and harness also. Three leads from the "out" side of the plug already connected to the pump. Ground from "out" side connected. I have been unable to locate any harness plug already in the car that would just plug right into the control unit. If it were there, there should also be a plug or junction to go to the vacuum pump, but no sign of that either.

Orange, green yellow and red yellow. These were wired via a separate harness to the vacuum pump. Reconnected the same way.

White black and blue black are on a separate lead to the pedal plug. Done.

There is a third plug from the control unit that plugs into the stalk switch (from same donor). That's also connected. No leftovers to account for the blue/yellow from the black 8 pin plug!

From the "out" side of the black plug that leaves the blue yellow, the red blue and the yellow. The yellow has a female spade on it, but no terminal on the back of the instrument cluster to plug it into (I remember there was one on the donor.)

I have spliced into the black/blue on the speed connector with a male spade terminal waiting for a friend to connect to. To the yellow female spade?

Thanks again to anyone to can help!!!

DS

Argh! See my note to Jessie. Finally found all the existing plugs. Found my notes, system came from a 91. With plugs located all is in place ready for a test drive. I note that the switch for the clutch pedal is hard up against the AC duct. Perhaps there is a shorter one for this position, or maybe that's just the way it is.

Thanks for helping with a brisk slap in the face via e-mail. Sometimes that is what it takes!

DS

Thanks. I mistakenly assumed that the system after 86 would drop in as well. As yet I've not found a 91 to scavenge from. However the 91 diagram shows the same eight pin plug plus one wire on the control box. When you say prewired, do you mean that the junctions and such are already in the 91? I could not find any of the junctions noted in the 91 Bentley diagram. For example, nothing in the area of the instrumentation to provide a speed pickup unless that comes from those two male spade terminals on the passemger side of the speedo that usually have a tubular insulator wrapped around them. The diagram shows a junction off the bottom of the brain (item 171) which goes to 241/34, a terminal on the Injection CU and also a split to 10/6 which I assume to be a fuse. I don't know if that is power or speed though.

Thanks Glen. I'm somewhat familiar with this setup from an earlier 240 I had years ago. Multiple relays and such. Unfortunately this one doesn't match! I think I need after 83 but before 90.

Regards,

DS