Regulator/Rectifier Issues

[Murray]

2009 DF90A 120 hours.

Last summer I was getting an intermittent 1-1 code, Rectifier/Regulator overcharging. Code would only come on at low RPMs and only occasionally. Bring the revs up to 3000ish and code would clear. Running above 3000RPMs would never get the code. Fast forward to this year the engine has been running flawless including trolling until recently, I’m getting a code but not the full 1-1, a beep and a single flash intermittently. Wife is steering and working the throttle while I’m in contortionist mode reading a CHEAP analog multimeter at the battery terminal. With the tachometer emitting a code, again intermittently I watch my multimeter go from about 14 V to pinned at 15V (VOM is on 15DCV, next scale up is 150 DCV) she applies throttle code disappears and VOM settles down to about 14.3 VDC. Battery is in it’s second season and has never been frozen, measures a bit above 13 VDC with engine off. This year I did notice the tachometer fluctuating 200RPM, the engine isn’t surging, just the tachometer and only during the intermit code.

Below is a picture of the service manual with my resistance testing. All numbers are on the 1K setting. I am using a cheap VOM not the “Suzuki pocket tester” Are my reading valid? Test didn’t turn out like I suspected and looking for suggestions. I did notice a uniform grey “coating” on all the spades in the regulator including the one opposite of “C” which is not used so I don’t think it’s corrosion. Thanks.

39422EB9-C956-455B-96E7-15445A25C92F.jpeg

[briscoe]

I'm not Red Lowery, but a voltmeter is a voltmeter. When it's supposed to read infinity it should not read ohms. It appears the rectifier is bad. The instructions say that values outside their specs means bad unit. That was easy. .... buy a new one.

[briscoe]

Murray, I was rushed on the post but wanted to follow up with my limited understanding of ohms. I believe when meter reads infinity it is not seeing any resistance. However, as it begins to see ohms (resistance) it means something is not working in the part. 4 ohms is not much, but it's not supposed to read anything, no continuity. No, I will not be teaching g at the community College this semester.

[Murray]

I plan on ordering a new one but mine is in specifications, sort of, only on the wrong spades, a mirror image of the service manual. With my cheap VOM I can’t measure the charging coils at 0.1-0.3 ohms, if I can find a digital multi meter in town I’ll pick one up. The local Suzuki dealer is a agricultural implement dealer and their mechanics are trained in agricultural machinery not Suzuki but they have agreed to confirm my readings and will check the new regulator vs the old one. There thoughts is possibly a misprint in the service manual or my regulator is on its way out.

[cprice11]

Infinity on the meter means no current is flowing through the meter as in open circuit, maximum resistance. Zero ohms or low ohms means relatively lots of current from the meter battery is flowing through whatever you are testing.

[redlowrey]

This one would be a good case study to see what is actually happening, the voltage has to go over 16 volts to log a code, why does it happen at idle and not at high rpm. This is where you would set up a volt meter, amp meter, and oscilloscope, and watch it unfold live. It would be interesting to see how much AC ripple was sitting on the DC.
As far as the readings go they don't look right to me, it tells you in the specs about the regulator having thyristors in the circuit and not to use anything but a suzuki pocket tester. I don't think I would use an analog volt meter to test internal circuits on a voltage reg.

[Murray]

Infinity on the meter means no current is flowing through the meter as in open circuit, maximum resistance. Zero ohms or low ohms means relatively lots of current from the meter battery is flowing through whatever you are testing.

Yes, I realize that. What is confusing me is based on my test results my regulator/rectifier shouldn’t be working at all yet it is still charging the battery at revs above 2500RPMs 99% of the time and 100% at higher RPM with no codes.

Suzuki want $445(Canadian) plus shipping while it’s $224US. I like to shop local and support our Suzuki dealership but double the price…We’ll be in the states in November so I’ll get one then unless I can find an aftermarket replacement.

[Murray]

This one would be a good case study to see what is actually happening, the voltage has to go over 16 volts to log a code, why does it happen at idle and not at high rpm. This is where you would set up a volt meter, amp meter, and oscilloscope, and watch it unfold live. It would be interesting to see how much AC ripple was sitting on the DC.
As far as the readings go they don't look right to me, it tells you in the specs about the regulator having thyristors in the circuit and not to use anything but a suzuki pocket tester. I don't think I would use an analog volt meter to test internal circuits on a voltage reg.

The bold print makes it clear that only a Suzuki pocket tester should be used for accuracy purposes, I get that. What has me confused is getting resistance readings where I shouldn’t and not getting readings where I should even if the readings are wrong. I did buy a digital multimeter today that has more features than the $20 analog but without the Suzuki pocket tester I’m guessing I’m no further ahead. I need a better multimeter at the cabin anyways. Boating season is soon coming to an end so if I can keep the voltage down I’ll replace the regulator/ rectifier on our next trip to the US. If I can’t then boating season will be over, When I replace the regulator sometime over the winter and install it next spring I’d be more than happy to send it to you. No charge, cheaper than Walmart!!! I’ll pull the ground off tomorrow and check that the contacts are clean.

[richardbjelland]

I am working on a df 90 model year 03. The up down ptts were in a fire. Lower one was the most burned. Does this happen regularly? ordered new parts, wanted to see a picture of wiring if one is available. Thanks.

[richardbjelland]

meant to add any help is appreciated.

[richardbjelland]

Had another thought, what would cause the relay, lower unit to catch fire?

[redlowrey]

Yes, I realize that. What is confusing me is based on my test results my regulator/rectifier shouldn’t be working at all yet it is still charging the battery at revs above 2500RPMs 99% of the time and 100% at higher RPM with no codes.

Suzuki want $445(Canadian) plus shipping while it’s $224US. I like to shop local and support our Suzuki dealership but double the price…We’ll be in the states in November so I’ll get one then unless I can find an aftermarket replacement.

Murray I have never used a suzuki pocket tester, but I would imagine it would be like a transistor tester thyristor tester, than an ohm meter. If you had a DC amp clamp or an amp meter connected in series with the output, and your voltmeter connected, you would be able to at least see how much current and voltage is being produced. My guess the output is dropping off at high rpm and the voltage is dropping below 16 volts. Put a small load on the battery and see what happens to the voltage.

Now that you have a digital multimeter spend another 50$ and buy a dc amp clamp, that way you don't have to break into the circuit to see how much current is being produced. Any person that wants to be able do some basic electrical problems should own one.

[Murray]

Murray I have never used a suzuki pocket tester, but I would imagine it would be like a transistor tester thyristor tester, than an ohm meter. If you had a DC amp clamp or an amp meter connected in series with the output, and your voltmeter connected, you would be able to at least see how much current and voltage is being produced. My guess the output is dropping off at high rpm and the voltage is dropping below 16 volts. Put a small load on the battery and see what happens to the voltage.

Now that you have a digital multimeter spend another 50$ and buy a dc amp clamp, that way you don't have to break into the circuit to see how much current is being produced. Any person that wants to be able do some basic electrical problems should own one.

Thanks for the reply, I might be able to borrow a clamp meter but I think his is only good for 10 amps, If I’m reading the wiring diagram correctly there is a 40 amp fuse in the charging circuit so the clamp meter would have to be able to handle 40 amps? My electrical knowledge is lacking, only very basic stuff.

[richardbjelland]

can anybody address the ptt issues on a df 90? had a fire on the lower switch, wonder why?

[Moonlighter]

can anybody address the ptt issues on a df 90? had a fire on the lower switch, wonder why?

Please start a new topic with your issue.

It just confuses things to have multiple different issues being discussed on one thread..

Its very easy to start a new topic.

Just go to the main page where all current topics are listed and click on the New Topic button its highlighted in pale blue, just beneath the Red Threads header) and go from there.