1992 S60 Governor/Actuator

[willie59]

I'm trying to keep this simple M, intentionally ignoring some terminal connections to paint a clear picture, you want to do voltage test under load, switches activated, not wires disconnected, when you're looking for voltage drop. What you basically have is power going from positive battery terminal to circuit breaker (again, I'm leaving out some terminals). Test voltage (under ignition load) at battery terminal, good voltage, move to circuit breaker. If voltage good at breaker, move to power input terminal of e-stop. If voltage good, move to power output terminal of e-stop. If good, move to input of selector contacts. If good, move to output terminal of selector contact that is switched on. If voltage drops at that terminal, you have a poor conductor inside that contact block causing voltage drop.

[M1687]

I'm trying to keep this simple M, intentionally ignoring some terminal connections to paint a clear picture, you want to do voltage test under load, switches activated, not wires disconnected, when you're looking for voltage drop. What you basically have is power going from positive battery terminal to circuit breaker (again, I'm leaving out some terminals). Test voltage (under ignition load) at battery terminal, good voltage, move to circuit breaker. If voltage good at breaker, move to power input terminal of e-stop. If voltage good, move to power output terminal of e-stop. If good, move to input of selector contacts. If good, move to output terminal of selector contact that is switched on. If voltage drops at that terminal, you have a poor conductor inside that contact block causing voltage drop.

Thanks again Willie.
I have been doing all of my testing with simply the selector switch on/off etc. I haven't checked anything under load. My assumption was that I didn't want the alternator voltage to over ride anything etc. So I learned something new. I'm sure I'll have more to come but I'm still knee deep into this issue. Thanks for your help again.

[willie59]

I don't mean with engine running M, you would get input from alternator then, I'm saying you test circuits for voltage drop using some form of load, such as ignition turned on, not running. The reason for this is a resistive conductor (bad wire, bad connection, bad contact) can show good voltage with no load on circuit. Since it's resistive, the only time it will show a voltage drop is under load, because the conductor is resisting flowing current to the component that is demanding the load.

[M1687]

Willie,
I'm glad you clarified that. I was out this morning and everything was good with the engine running. lol.
Up until this morning all of my readings were with the key switch on/engine not running. Every once in a while I start the engine to keep the battery voltage up but then shut it down for testing etc.
Hopefully I can narrow down my issue which appears to be near the upper E-stop area. I have a question regarding the indicator lights. If these go bad will they cause a drop in voltage theoretically? Can the internal connections cause the electricity not to flow through? As far as replacements, are they anything special or should I order from the local dealer just to be safe?

[willie59]

M, I've been going back over this thread trying to determine exactly what you're working on (problem) at present, aside from the voltage drop that you've stated. If you could give me a brief summary of what you're chasing, might help.

As for voltage drop along circuits, don't know if it's you problem, but those Telemecanique contact blocks are notorious for causing voltage problems. You can switch on upper or lower one time (makes a connection inside contact block) and it connects good. Next time you activate contact, it doesn't make good connection inside. I used to carry a good supply of those contact blocks on my service truck when I used to work on those things.

[M1687]

Willie,
My overall problem is that I have burned up two new/rebuilt controllers (the outputs). The supplier feels this may be caused by a bad actuator and/or hooking up the controller with the battery on etc.
I've hooked up both with the battery off. I tested the actuator and have a good ohms resistance of 3.2. Looking over the Precision Governor manual it states that on terminal one and two I should have the same voltage as the battery voltage. This is what I do not have. There is a drop in voltage at terminal one and two with the key on/engine off. So I've been searching around that primary circuit trying to find why I have a reduced voltage etc. I first started from the controller and went backwards etc.

[willie59]

M, I've been working on these things for years, never burned up a Precision Governor controller from bad actuator or other quirks of wiring, this is territory I've never experienced, that's not to say what you've stated is not the case though.

Just to clarify something, terminal 1 and 2 of controller, terminal 1 is battery positive voltage terminal for sure. If I am reading schematic correctly, term 2 is ground terminal. When you say "the Precision Governor manual it states that on terminal one and two I should have the same voltage as the battery voltage."

Are you saying you read voltage on terminal #2?

[M1687]

Willie,
With the key on (engine off), I have a reduced amount of voltage when the positive probe of my multimeter is touching terminal #1 and the negative probe is touching terminal #2. I've tried using the common ground with the negative probe thinking I had a bad ground etc. I still have the same scenario.

Also keep in mind I did find a major short in the wiring which was leading up to one of the beacon lights which is in that circuit that feeds terminal #1. My gut feeling is that when that wiring shorted out, it took something else with it along with the controller? So when I hooked up the new controller it shorts out immediately as soon as I turn the battery on and key switch etc. I don't know alot about these controllers but the supplier told me they bench test these units with an actual engine before they ship them out. I'm hoping I can find what else is wrong in this circuit, then I will send the controller back one last time and hope for the best?

[willie59]

M, lets try something just to get you going. I suppose there is a possibility that a wiring short on the circuit that powers terminal 1 of Precision Governor could have trashed it, never seen that so can't say for certain, but your reluctance to fry another one from a problem on that circuit is understandable. So...let's insulate the Precision Gov from that circuit. Install a Bosch cube relay using diagram below. Connect the red/wht wire that is supposed to connect to term 1 of Prec Gov to terminal 85 of relay. Wiring this relay to Prec Gov will do three things, 1) insulate the gov controller from suspect circuit, 2) remedy any voltage drop on that circuit powering relay as these relays demand only milliamps of current, and 3) provide good voltage to terminal 1 of gov controller as you're getting power on 30 of relay from a good battery source like battery connection at starter.

[M1687]

Willie,
I'm willing to try anything at this point. Currently I have a "bad" controller on hand so I wouldn't be able to see if this scenario would work until I get another one etc. The red/white wire you want me to hook up to 85 on this relay is where I have the reduced voltage/possible short. You're saying this won't effect the controller because the relay is insulating it?

I did some more poking around the machine today. I still have something going on with the circuit that has the indicator lights for the oil/water. More so on the water temperature. I'm still unable to isolate it though. I have a question for you, when you turn the key on/engine off and the indicator lights come on for the oil/water, what component in the circuit makes them turn off once the engine is started? Is it the switch gauges? I had something new happen today when I started the engine my water temp indicator lights (both ground and platform) stayed on after the engine was running etc. More to come as I work on that tomorrow. Thanks.

[willie59]

I'm saying the controller won't be adversely affected by a fault on red/wht wire circuit because controller will now be getting power from another (more reliable) source. All the red/wht wire will be doing now is activating the relay, if a fault smokes it, big deal, you're out a couple of bucks as opposed to a toasted controller. And the more I think about it, you should connect term 1 of governor actuator to term 87 of relay as well because term 1 of actuator is powered by same circuit as term 1 of controller. You said you want to get this wiring thing figured out before having controller repaired again. I'm saying, go ahead and get your controller fixed, install it, and wire it up to the relay, now there's no danger a fault on red/wht wire circuit is going to smoke repaired controller and you can proceed with your troubleshooting.

As for your temp light, according to the wiring diagram, that light should not come on when you turn the ignition on as the light should be controlled by switch gauge, only time that light should come on is when the contact inside the switch gauge closes the circuit from temp being high. At least that's what the diagram shows. Oil pressure light should come on when you turn on ignition, then go off once engine gets running an makes oil pressure.

[M1687]

Thanks again Willie. This makes sense regarding the wiring of the controller. I don't know a lot about these controllers but I'm assuming they sense a drop in voltage as to when to increase engine rpm? Possibly measuring the hertz? Will this be affected using this cube relay you think?

I think you just resolved one of my problems. Looks like a have a bad water switch gauge as the indicator light comes on with the key on/engine off and now while the engine is running. I'll have to study the diagram to see how this affects the circuit for the controller etc.

[willie59]

The governor controller makes adjustments to engine throttle via actuator depending on inputs from ignition coil on terminal 3 of controller, this is separate circuit from power input circuit on term 1.

[M1687]

Hey Willie,
Well, I pulled both wires off the water temp. switch gauge and didn't resolve my one issue etc. Looking at the diagram I'm trying to see where power/backfeed would exist on both upper and ground control indicator lamps at one time. It seems as if TR2 may be a possibility along with a bad diode. Or possibly TS 5 or TS13? I have to believe that there may be some damage to the controls in the platform since this thing may have sat outside for a while? I'm probably going to try one last thing before I wire it up the way you suggested and thats just throw some new parts at it which is common for an amateur like me. I was thinking a new TR2, TS5, TS13, selector switch, and both e-stops? I've had bad luck with Telemecanique contacts before also. My situation was with a Powermatic Model 66 table saw that wouldn't turn off etc. Kind of scary...