I have a 90 Acura Integra and the cruise stopped working all of a sudden. It will not "set." Using the wiring diagrams, I have checked all of the wiring to the cruise control unit and they all look OK. There are 2 inputs that I do not know how to test and was wondering if anybody had any info. The "blue wire from the ignition control module had ~14 volts coming to the cruise unit while the engine was running and did not seam to change as the RPMs changed. The orange wire from the speed sensor had 2.1 volts and also did not change with vehicle speed, although it did drop to zero when stopped. Any ideas how to test these 2 inputs? Or is it time to get a new cruise control module? Thanks, Todd
+++++++++++++++ First and easiest place to check is the brake switch, since it's one of only three or four 'moving' parts. If the unit is turned ON, at the dash switch, but thinks you've got your toe sitting on the pedal, pushing the steering wheel cruise button won't set the speed. 'Curly'
I agree with Curly about the brake pedal switch. To elaborate, the switch is usually the same as the one for the brake lights, but there are two sets of contacts in it. It is possible for set of contacts for the brake lights to work while the set for the cruise does not work. Also, if your car is a stick shift there is another switch at the clutch pedal that could be faulty as well. The clutch pedal switch could also just be out of alignment (if the brake pedal switch was out of alignment your brake lights would likely be on all the time). Testing the VSS signal is simple. Measure the voltage while slowly pushing the car forwards or backwards. You could jack one front corner of the car and rotate the front wheel with the car in gear also. You should see the voltage alternate between some voltage (5V on my car) and close to 0 Volts as you move the car (or rotate the wheel).
I checked the brake switch and it seems to be working properly. According to this web page http://www.hondahookup.com/manuals/Wiring%20diagrams.pdf it is a DPDT switch in which only one leg has power at a time which is what it is doing. The clutch switch does not have any power coming to it. I thought it might get energized when the cruise is set; which it is not doing. I will check the speed sensor. Any idea on the blue wire from the tach? TIA
I don't know as I've never measured the clutch switch, but it could be a ground system instead of 12v. Try using a multimeter with red to constant 12V and the negative probe to the switch. See if the meter reads/doesn't read 12v depending on the switch position )or use the meter in continuity mode substituting a good/known ground for the 12V mentioned above). As for the Tach wire. If it is the same as reading Tach directly from the coil, put your red probe on 12V constant, set the meter for AC voltage and probe the tach wire with the black probe. If it is a Tach wire the meter will then read some multiple of near true RPMs.
Todd, Does the indicator light in the cruise control main switch come on? What happens when you depress the "set" button? If the cruise indicator in the gage assembly comes on (even for a fraction of a second), the problem is most likely in the cruise actuator or actuator wiring. -- Tp, -------- __o ----- -\<. -------- __o --- ( )/ ( ) ---- -\<. -------------------- ( )/ ( )
The Main switch is ON and the LED is ON. The indicator light never comes on at all; not even for a fraction of a second. When I press the "set" or "resume" buttons, I do get voltage coming to the correct terminal on the cruise control unit. I checked all of the continuity between the actuator wiring and the control unit. All looked good. Any other ideas? Thanks, Todd
Well I finally figured it out, and your not going to belive it. After all of the checking of wiring, voltages, switch continuities etc. it turns out that the clutch switch was not engageing. The "plate" on the clutch pedal itself that activates the switch had a hole in it. The pin switch button went right through the hole. BTW, this thing is sheilded from view by the bracket that holds the switch, so it was impossible to see. There was probably some kind of plastic "something or another" that went into the hole and activated the switch. I ended up putting a small bolt and nut in the hole and covering the bolt head with a piece of foam tape for padding. Works great now. Now here is the funny part. I really thought it was the Cruise Control Module so I bought one off of Ebay for $20. Just as I was buttoning the project up, the FedEx truck shows up with the new module Go Figure. Thanks for all the help. Todd
You obviously know your way around a circuit diagram. Have you tried measuring the voltages on the wires from the clutch and brake pedal switches (measured at the control unit)? Ignition on, cruise control unit plugged in and cruise control master switch on. There should be one wire for the clutch and two for the brake. I believe (but am not certain) that you should measure battery voltage on the wire from the clutch pedal switch when you are not touching the pedal, and 0V when you are stepping on the clutch. Both voltages referred to body ground. For the wires from the brake pedal, one should carry battery voltage while the other is not. Stepping on the brakes should reverse this. If you try measuring the voltage on the wire from the clutch pedal switch, the control unit needs to be plugged in and turned on. If this is a pain, you can measure continuity to ground on that wire at the control module end of the wiring harness, with the module unplugged. There should be continuity to ground when, and only when, you are not stepping on the clutch.