Well, I finally got the cruise control working. The problem was a broken wire in the turn signal stalk.

In one of my earlier posts in this thread I mentioned that I was not getting the 1-1-3 code and I thought it was because I do not have a clutch switch (automatic car). Well, 1-1-3 code is very important, it turns out. The FAQ was not very clear on how to test it. It says: "Depress brake then clutch pedal for a second" in the action column. Well, if you do that you will get the brake pedal code, 1-3-2, which is what I got. Turns out the 1-1-3 code is generated every time the switch goes from ON to OFF and from OFF to ON. This was not at all clear. The FAQ should say in the action column: "Move the selector switch from ON to OFF or from OFF to ON" to obtain 1-1-3 code. Also, in the Fault column it says: "if no code:brake and clutch valve" This is incorrect. No 1-1-3 code means no power to the control module. I was able to learn that in the cruise control diagnostic procedures for 850, which is similar enough to have helped. This is the link to the PDF with 850 diagnostics: http://www.volvoclub.org.uk/tech/service/850/CruiseControlSystem.pdf

1-1-3 was the only code I was not able to get in the diagnostic mode 2 (socket B2).

So, it took me a long time to arrive at this. I suspected the control module, so I removed it, opened it, examined it and found nothing suspicious like burned components or traces. I saw a relay there and traced the switch to the yellow/red wire in the connector, which is the wire going to the vacuum pump's bottom wire. That is supposed to be +12V. I had nothing on that wire. I soldered some wires to the control module such that I could drive and have my voltmeter connected to the vacuum pump +12V. I drove and tried setting the cruise control and got zero on that terminal. This led me to thinking I was not getting power to the module's vacuum control circuit. That's when I started looking more into the 1-1-3 code and found the 850 diagnostic routine that explained it a bit better than our FAQ. It clearly says that 1-1-3 code is produced when the selector switch is moved from ON to OFF or from OFF to ON. I did not get that and that's when I took the shroud around the steering wheel off and saw the broken blue/green wire staring at me. It was broken right at the edge of the plastic covering the stalk, but I was able to strip enough of it to be able to solder it back and apply some shrink tubing to the solder joint. As soon as I did that I got the 1-1-3 code and the test drive confirmed perfect operation of cruise control. My repair of the pedal valve with teflon tape is working very well so far. I went up a hill that caused the cruise control to slow way down before it died all together (from the broken wire). So far so good. I buttoned everything up and all seems well with the cruise control.

Whew! That was a hard one. Mainly because I was misled by the FAQ's explanation of the diagnostics. Is there a way to change the FAQ to be more clear? I would be more than happy to do it.
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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 - hers