Cruise Control Troubleshoot

Started by rednucleus · Dec 18, 2011 · 12postsSMF 2010–26

rednucleusDec 18, 2011, 8:31 pm · #1

My dash indicator light turns on when the switch in the turn signal is pushed, but the unit does not engage. No response when pushing the accelerate switch on the turn signal either. This started before my engine change. Electrical & vacc connections are good.

ProlowtoneDec 18, 2011, 8:52 pm · #2

I thought mine was broke but got it to work one day. Turn cruise control on, Hold accelerator steady as you hold in the button on the end of the turn stalk for a few second, Let off accelerator, Enjoy. If that dont work then you may have a bad fuse,wiring or the diaphragm inside the unit (I think it has a diaphragm).

rednucleusDec 18, 2011, 10:40 pm · #3

I'll try tomorrow and let you know, thanks

Post Merge: 10:30:01 AM / 19-Dec-11

Pro - tried your suggestion, didn't work though. Speed sensing seems to work because it wont light below 30 mph, so guessing it's in the cannister motor thingy vs the electronics?

Cajun1guyDec 21, 2011, 7:52 am · #4

Check down at brake and clutch pedals. There is a rubber button in the pedals that is supposed to hit on the disconnect switches, if they are gone cruise won't come on. You can still get those from Nissan, or you could wrap a large tie rap around the pedal arm and get it to hit the switch when the pedal is released. May have to adjust the switches to get engagement.

rednucleusDec 21, 2011, 10:00 am · #5

Thanks Cajun - the light comes on showing engage when the button is pushed, and goes off when brake or clutch are hit, so that part of the circuit seems fine - just no actual response from the motor/servo. Any way to troubleshoot the servo - "hotwire" it to see if it works in the driveway?

ProlowtoneDec 21, 2011, 11:43 am · #6

No clue, but check the thin vac line, and small crack will mess it up pretty good

rednucleusJan 11, 2012, 5:00 pm · #7

Got my FSM on Ebay and it has a great section on troubleshooting the cruise components. Hope to do it tomorrow. After reading I think it's a bad actuator. I'll eventually post the pages for anyone interested. Any body got a working actuator they want to unload? One other thing - the manual talks about a seperate vacuum motor for the unit - mine (85) gets vacuum off the engine.

Cajun1guyJan 17, 2012, 10:14 pm · #8

The servo does get vacuum from the engine normally. But when you accel the vacuum goes bye-bye, thus the electric vacuum pump. It is located in the right rear corner of the engine bay near the wiper motor. Ashley was just having one of the servos for sale, but i think she dumped whatever did not sell the other day. I found a servo "Like new" a year or two back, someone is always tossing them out as they lighten the car up.

rednucleusJan 17, 2012, 11:02 pm · #9

Mine is working again! Performed the FSM test on the servo by hooking 12v to it and the valves clicked back to life and started working great. I'll get some pics of the FSM trouble shoot in here sooner or later. Still don't think I have a vac pump but I will check again after the stupid snow melts. Got 8" today - that's enough to shut most of Western WA down - drivers around here have no clue what to do when it hails hard, let alone snows.

Cajun1guyJan 18, 2012, 9:22 pm · #10

Oh wait! You have a CA20, right? The vacuum pump only applies to the CA18 Turbo setup. Brain fart...

rednucleusApr 10, 2012, 9:47 pm · #11

Here's the '85 FSM ASCD pages. Sorry, forgot to put them in in Jan

posted image

mentalxpreshunApr 11, 2012, 1:04 pm · #12

Sweet... this will be very useful, as I would like to get my Cruise Control working again, or at least testing it out. Both my 84's have it, but one will be spare as one will be a trackwhore =P