Yamaha Drive buzzing noise

[tomtt2]

I have a 2007 Yamaha Drive (48 volt). When I first turn on the ignition switch, the solonoid clicks (as it should) but I also hear a buzz or hum noise for about five seconds, then it disappears.

If I lightly depress the accelerator pedal (enough to click the solonoid but not enough to make the cart move) I also hear this hum noise. Actually, it's there anytime the pedal is depressed, just hard to hear while moving.

The dealer has replace the solonoid twice (I'm on my 3rd one), but the noise continues. I'm not sure it is actually the solonoid.

Could the regen section of the motor or the control unit be causing this noise?

I've checked several neighbor carts (also Drives) and after the initial click of the solonoid, all is silent. I also checked some of the carts on the dealer's floor--same thing, no hum.

Besides being annoying, I wonder if the hum is somehow related to the range of the cart on a charge. I check the battery water every other week, use only distilled water, and plug the cart to the charger after every use, still, my range appears to be significantly less than my neighbors.

The Trojan batteries are less than one year old, so they shouldn't be sulfated or otherwise compromised. I'm wondering if this hum is causing some kind of additional current draw resulting in the reduced range on a charge.

Has anyone else with a Drive had this "hum" issue?

[COURTESYCART]

i havnt heard one hum, but it shouldn't be too hard to diag. Remove the rear access cover and make cart hum and use a mechanics stethoscope to find noise.

as far as run time. I will say TROJAN 12V are junk. US battery has a better 12v battery.

[scottxray]

Tom,
My 2010 was also displaying the exact same symptoms as yours (hum 5 seconds at key on and lightly depressed pedal) when I first got it home 2 days ago.

However, after I had fully charged my batteries for 2-3 complete cycles on the factory charger the hum has quit completely. I know that the seller had had the batteries discharged to the point of the charger not starting the charge at one point in the last few weeks. So, perhaps the hum has something to do with the unequal charge, although the controller shouldn't be able to see it.

The first cycle it still remained, and the charger did not display charged, but had a blinking power Led when I checked it later. However the bank measured 51.5v. I then took it out at night and ran with the lights on for about two miles. The second charge the Charged light came on and stayed on.
Hum was gone. Third cycle ( after 2 mile run) the same. Yesterday I played nine holes ( fairly flat course) and visited a couple of close by friends and checked the charge when I got back ( 49.1 volts so about 62%). Charged and got charged light steady again.

When I first got the cart there were voltage differences between the outer and inner two batteries of about .25 volts. After the several charges the batts are all within .1 volt 6 hours after charge. If you have a voltmeter you might want to look at that to see what yours are.

I haven't found a manual for the stock 2010 Drive charger yet ( does anyone have one?) and don't know exactly what the light sequence is, or what might be considered normal end of charge. I would think that it should stay on with the charged light lit. If yours is not then perhaps there is a problem with the charger?

The sequence mine seems to go through is:
Power Led on ( 110 connected)
Flash all Leds for ~ 5 seconds at connection
Charging Led on ( blinking)
Charging Led on steady (70%?).
Charge Led on and Charged Led blinking ( 80%?)
Charge led and Charged Led both on (90%?)
Charged led on (100%)
The voltage mine puts out cycles up to about 56.8 v at about the 80% point and then cycles back down to about 52 at 100%.

[tomtt2]

Wow!! Scottyxray...........absolutely outstanding response.

I received my cart back from the dealer a few days ago. They replaced two of the four batteries. That was a little troubling since the batteries are only about 11 months old and I check the water at least every other week and use only distilled water. I also hook up the charger every time I pull into the garage.

Anyway, the dealer also replaced the solenoid (again) and after I fully charged the cart, the hum seems to be gone (I think....).

The dealer said they talked to Yamaha Tech and they though that maybe the solenoid issue was due to not setting the parking brake when I stopped. Unfortunately, that is definitely not the case. It's pretty hard "not" to set the parking brake since the little square is so easy to hit by mistake.

I'll print ouff your post so I can do the voltage checks. I have a good (Yamaha) volt meter I can use.

One thing I did notice when the cart was returned was the mileage per charge. Now I get what I think is "normal" MPC. Before, my neighbor's Yamaha Drive seemed to be getting a lot more out of a charge that I was. Now I think we are about equal.

I'll post result as I move forward. Thanks a million for taking the time to do a detailed posting.

Regards,
Tom T

[scottxray]

Tom,

Went to the dealer and got a manual on the charger today.

I had the wrong guesses about the Leds.

Manual states the following:

5 step charging cycle
1. Pre Test . Yellow Led blinks on and off Applies tests to the battery pack to see if charging is prohibited ( over/under voltage, reversed battery leads etc.

2. Constant current charge. Yellow Led illuminates continuously (indicates batteries are being charged at full rated output.

3. Constant voltage charge. Charge current is gradually decreased while voltage is held constant. Yellow Led on, Green Led blinks.

4. Top off. Yellow and green leds on constant. Pack at 90% capacity. This ends when the pack is at 100%.

Charging is completed when only the Green led is on.

If the charger detects that the battery needs to be boosted ( equalised) then the pack continues to operate for an extra 4 hours . During boosting only the power led blinks . Note that I was told by the tech at yamaha that this could take up to 20 hours.

5. Storage. After completion of step 4 and after 14 days time has elapsed, AND if the battery falls below 48 vdc the charger will restart a new charge routine.

Disconnecting the charger from the cart always resets the charger and it will start at step 1 .

I also have the error codes for the charger. ( and the rest of the manual.

I will scan it to PDF and send it to you later if you'd like.

[tomtt2]

Thanks Scottxray. I would love to get my hands on the manual information you quoted.

I found the complete Yamaha Drive manual in pdf form on the Yamaha web site. I may cough up the $48 bucks they want for the pdf version of the manual.

Thanks for the diagnostics you've provided.

Regards,
Tom T

[COURTESYCART]

YAmaha also has issue with their chargers. I have seen several cut off to early and not fully charge the battery pack, Not to mention, if you have the Trojan 12v batteries, IMO they are junk right off the pallet. Trojan only builds good 6V batts.

[tomtt2]

Thanks Courtesycart,

The batteries are only 11 months old, so they will stay in place for a while. If they fail, I'll try to get an non Trojan replacement.

How common is the Yamaha charger early-turn-off issue? Is there a test for the problem?

Thanks again,
T

[scottxray]

Originally Posted by COURTESYCART

YAmaha also has issue with their chargers. I have seen several cut off to early and not fully charge the battery pack, Not to mention, if you have the Trojan 12v batteries, IMO they are junk right off the pallet. Trojan only builds good 6V batts.

CC,

The Trojan 12volts ( T1275) apparently are okay for personal carts.

The main thing with the 12s that caused problems ( and this applies for CC and Ezgo too) are the carts that went to courses for fleet use. Most courses want to run the carts for two full rounds a day between charges, and the 12s will be discharged to about 25-30% by that vs about 50% for the 6x8v systems. That kind of use cuts the battery life significantly, hence the reason the 12s got a bad rep. Plus apparently ezgo got a bad batch of Blackcased 12 volts ( special just for CC) that WERE crap and started the reputation problems, as well as the lawsuits by CC and Trojan against each other. That is what gave the other manuafacturers their foot in the door vs trojan.

US does seem to make a good battery too, and now runs neck and neck with Trojan. Apparently CC is using Crown batteries in their new carts according to some reports.

I agree that 6x8v gives more reserve and therefore keeps the charge up higher. That means longer life as the discharge is less, since they have higher capacity than the 4x12 config ( or a 6x6v config). I will definitely go to a 6x8v configuration when I need batteries. Whether US or Trojan I would expect similar results, but the Yamaha charger manual also states that the charger should only be used with Trojan batteries.

A better or OEM charger may also be indicated if there are problems with undercharging, as you state....This also will make any battery fail earlier than it should.

My Yamaha dealer says that the T1275s are lasting about a maximum of 5years on personal carts, vs 6-7 on 6 battery packs. Yamaha also changed to the 6x8v config that CC and Ezgo both have gone to, in 2011, and are definitely still using Trojan batteries and giving a 4 year warranty on the batteries also, on new carts. That would tell me that its the 4x12v config ( not necessarily the Trojan batteries) that caused so many problems.

Since most courses limit the speed to 12-15 MPH, a private cart that has had a speed chip ( or PTV code), a lift, and maybe larger tires and wheels as well as other add in options ( lights , radios etc) may use as much power as a course cart that is governed in speed but run twice a day. That extra 5mph speed, especially, will draw the battery bank down at aproximately twice the rate of one running 14mph. It is a function of power to weight and speed ( kinetic energy). Hence, even private carts may see early battery failures due to heavy discharge.

At any rate IMO the Trojan 12volts are not bad batterys, and they will perform as well as any 12v, in a 4x12 config. But the life will not be as good as a 6x8v setup, as they will take deeper discharges. And of course proper maintenance is absolutely essential.

[tomtt2]

Thanks Scotty,

Excellent and thorough response. It sounds like the hot ticket in the future would be to switch from 4 x 12v batteries to 6 x 8v packs. That's a ways off (I hope), but I will keep the thought for when the time comes.

Since I don't allow my batteries to draw down too far between charges, it sounds like the Trojans will do okay.