Cookie_M0nster

Hey guys,

I'm coming back for some more advice about this '82 CE. I'm having issues with the cruise control system not engaging. I have done some extensive research not only here but else where on the interwebs. I have come across some good info but nothing that is directed to the '82 in general. I have printed out and been using this information here (http://www.splashedpaint.com/cameron...iseControl.pdf) as well as some fuse block diagrams, and ground distribution schematics. I have verified that the grounds are good, clean and intact. all the vac lines are in good shape, and the wires are connected to the proper places. But i am still having issues.

According to the website I linked above on the blue wire(Hold) going to the transducer I should have 12v when the cruise switch is released, 12v when it is in the second position, and 0v down in the trim position. It also states that at the green wire(Engage) I should have 0v at cruise, 12v at Engage, and 0v at trim.

I turned the key to KOEO and probed the green wire with CC on and the button depressed with my DMM and I had 11.24-11.30v, and at the blue wire I had nothing. I took it for a test drive and came back because It still would not engage. When I probed the wire again (KOEO and button depressed) I now have 4.25-4.28v at the green and ~0.04-0.11v at the blue wire.

I also have verified that the servo is able to move and the throttle plates open as they should. I couldn't find my MityVac in order to test for how much vacuum it will hold thought. I will test that tomorrow. All of the vac lines look brand new and are still pliable and show no signs of wear/cracking.

I am also curious about a **** that mounts under the steering column with two vac lines running to it. it is mounted in the removable trim surround that is attached to the dash where the steering column meets it. The two lines in question both have tracers one is blue the other is a tan/off-white. I traced them as far as I could and it looks as though the tan one runs up to the headlight actuators. Anyone have any thoughts as to what this might be?

Thanks for you time.

Andrew

DUB

Andrew,
The pull down **** under your steering column is another way for you to be able to raise your headlight doors WITHOUT pulling the headlight switch. It has nothing to do with the cruise.

One thing to check with your hand vacuum pump gauge is the vacuum line that goes to your brake switch under the column for the dis-engage for the cruise. If the switch is bad ( not able to hold a vacuum) or not set correctly...regardless of any electrical issues you have...the system will not work due to the system is thinking that you are applying the brake...and never engage and hold. I have repaired so many due to this issue I can not count.

DUB

Cookie_M0nster

DUB,

Thanks for the lead. Is there a specific value I should be looking for on the Vac pump? Also if I apply vacuum to the brake switch will the voltages at the transducer or the switch change?

Andrew

Cookie_M0nster

Update: I have tested the brake switch with the vac pump. The switch will hold 15in/hg for over a minute, and when the brake pedal is depressed the vacuum is dumped.

lvmyvt76

isn't there a switch by the brake light switch that breaks the electrical circuit when brakes are applied( the older car have this, thought yours would too) these get out of adjustment, wires knocked off, or broken sometimes.

Cookie_M0nster

I have checked the switch and everything seems to be working as it should. All of the connectors are hooked up and the brake lights come on like they are supposed to.

I took my DMM and checked the plugs that go in to the transducer. KOEO with the CC switch turned on I have 4.24v at the Green wires, and 0.01v at the blue. When the brake pedal is depressed the voltage jumps to 11.36-11.44v on the green wire and stays at 0.01 on the blue. When I push the set button on the CC stalk the voltage on the green wire goes to 0.01v and the voltage on the blue jumps to 11.44v. I have also ohm'd the transducer solenoid according to the procedure listed in the website I linked above. The link states the resistance should be around 5-7 ohms, and I have 7.12 ohms.

EDIT: I also checked for engine vacuum. I have a solid 19 in/hg at the manifold.

Lakeside49

The overwhelming odds are that your transducer needs to be replaced. I did it myself in my '82 a few weeks ago. It was gratifying to buy a reman transducer and do it myself one Sat. morning. Do a search on this forum for speed control (or perhaps 'cruise control') transducer repair (or replacement) as I posted my insights that you will probably appreciate and were fresh in my mind, then. It's a wonderful thing when the cruise kicks back in on your test drive when you are done!
On another note, buy/read your '82 owner's manual - obvious things like the headlight override switch are all in there.
Dave

7T1vette

Didn't the '82 have the same ECM as came on the '84 cars? If so, the [electronic] cruise control system should have been built into the ECM...not a separate transducer head.

Lakeside49

I guess it could have been a figment except that I woke up to an empty transducer package, a forum posting, bandaged knuckles and my cruise suddenly worked after dozing for quite a spell. I'll take those dreams any day if they would just leave out the pesky part about the overly-realistic charge to my credit card!
Sorry - getting punchy in this arctic air we can't seem to shake here in the Midwest