Can anyone tell me how to troubleshoot (or maybe I should go ahead and really "shoot" it) my cruise control? I only have a multi-meter and a simple test light, oh yeah, and a couple of "simple" brain cells left, so ifn y'splain it real clear, I should be able to do it. I sure do miss it on them long "trail drives" we have to make to git anywheres down cher in Texas.

I'm a-workin' without a net here, since I don't have a Volvo dealer willin' to help me and nobody else who'll tackle it. So, make it a "cookbook" procedure (y'know--first, y'do this, next, y'do that, etc.) Haven't found any books to tell me how either. Shore 'preciate it.

What part of Texas are you located? If you're anywhere near the DFW area, have you checked Southwest Auto?

I had cruise on my 80 and 86 (still have), and I remember relacing the throttle wire a couple of times on one of them. The 86, I think. Its a very thin braided steel cable that is easily missed and about as easy to replace. It is up under the drive's footwell and runs from the pedal to the vacuum control. Since the 84 fall between those odel years, I have no idea which you may have.

Hold up on clutch pedal with left foot while engaging controls. Clutch switch not being closed is a very common problem.

If you can lift your pedal up your clutch cable needs to be adjusted.

The switches on the clutch and brake pedals can move around and not be depressed when pedals are released (up).

The vacuum pump for power brakes is the same source as for cruise. I assume the brake pedal isn't hard indicating vac pump problem.

TT --

Is this your diesel, or is this a gas job?

Don,

Yep, it's m'diesel--th'only Volvo in m'stable.

What are symptoms? Have you narrowed it to electrical part or problem with vacuum holding? In the past I've had problems with adjustment of brake switch which won't let cruise activate if it's not right. Also on my '90 there is a small diaphragm near gas pedal (which holds vacuum for throttle cable?) which had a hole worn from pedal action. No vacuum= no cruise.

Any more clues?

Trey,

The only symptom is that it doesn't work. I haven't narrowed it down to anything--don't know how. I've looked under the hood and everything seems to be hooked up like it should, (vacuum was my first thought, fuse was my second, but those were okay. Still . . . something isn't doin' right. I just need to know what to look/check for and where. I've looked for books, I've looked for schematics, but no luck yet. At this point, I'm ready to accept any reasonable guess, so if you have one--shoot it to me and I'll get on it.

Trey, I had a similar problem with one of my 740's. Found that because of the angle of the vaccumn hose, and the age of the hose, it split at the diaphram connection. I not only replaced the hose, but made it longer; routed the hose to the pump so as to eliminate stress points. Otherwise, check the pump for vaccumn and the diaphram (actuator)for resonsiveness. Good luck

I have an '81 240 B21F Calif. in which the criuse control recently stoppped responding. I installed the system myself from a volvo dealers kit.

Instructions don't give much info other than where to install stuff and how to adjust. This system is I believe the "older" style. The vacuum servo is mounted under the wiper motor and has the brand name "Daton" on it. I think the newer styles had a smaller servo.

Anyway if this sounds like yours, the compontents are: servo, decel sensor ( a mercury switch mounted on a little angle bracket near servo and is normlly closed), and the cable. All under the hood. The control box is under the dash on the right side just behind the clove box. Then ofcourse there are the clutch and brake peddle(electrical and an air valve) switches and the control lever. There is an inline fuse on the control lever connector.

Typically one checks fuses, all connectors for tightness, and all switches for continuity. The vacuum servo has two internal electrical air valves. One opens the vacuum line to the vacuum source and the other vents the vacuum in the servo to the atmosphere thus moving the cable in or out. You can check these for continuity at the servo's connectors. If you think the contol box is bad, you may find another cheap in a pull-it-your self savage yard.