DF175 Revs and cuts off at startup.

[SLW2018]

I have a 2012 DF175. It runs great and has never given one minute of trouble. Recently I noticed it doing something a little strange and I wanted to see if anyone has any ideas. Motor cranks with no problem(soon as you turn the key). It then revs up to around 2000-2500 rpms on it's own and then drops down to an idle and below until it shuts off. No alarms, no Lights. I can crank it up again immediately and it will do the same thing, cranking everytime and eventually stalling out. If I want to get it to idle, I can put the shifter in neutral, add a little throttle as the RPMs are decreasing and then pull the throttle to neutral and it will idle perfectly and run perfectly. Just for the hec of it I looked at the IAC Valve to see if there might be something noticeable going on with it but didn't see anything. Anybody got any ideas? Also, could anyone tell me how the codes are retrieved? I don't have the so-called smart gauge, just light on my boat. Does the audible alarm sound out the codes?

[Harper]

Low voltage, because of low battery, or corrosion on battery and wiring terminals. White wire (called sub-battery cable by Suzuki) not connected directly to battery + or to battery switch output. Whichever the reason, it's due usually to insufficient voltage to the ECU. Causes your EXACT symptoms. Revs on start to 2.0-2.5K RPM and dies. So fully charge your battery, and check your wiring connections.

Don't make the mistake of assuming it's the IAC. It MiGHT be, but check everything else first. Insufficient voltage is a more likely cause.

[SLW2018]

Thanks Harper. I would sure have been on a Goose chase. So, this White wire(sub battery cable), where does it originate from? Can you point me in the general area? I have no manual so I'm working blind here.
By the way, got any pointers where I can get a service manual for it without having to mortgage the house???
Thanks again!

[Harper]

The sub battery cable runs from the start battery positive terminal OR from the battery switch, to the ECU power relay. That relay is activated by the key, and closes when you turn the key on. This assures that the ECU gets the full battery voltage when starting by providing a direct link from battery to ECU through the relay. There are other options for the wiring that a boat manufacturer or dealer might use. For instance, I had the exact problem that you're having when starting, and I could not find any white wire coming from the starting battery or from the battery switch. My boat is a center console, and the batteries are amidships under the console. As it turns out, the large battery cable (00 gauge) that comes off the battery switch goes to another positive bus bar in the transom and all of the power for the motor comes off that bus. That is also where I found my white wire connection. My problem turned out to be simply a battery not fully charged. I've since changed the type of battery switch, added the Suzuki dual battery isolator lead, and added an onboard charger/maintainer. Both batteries now get charged while running, and the boat now stays plugged in while parked at home. I've never had another starting issue.

Concerning the manual, I know it may seem like a lot, but I personally prefer a manual in print form, and would not look for a downloadable version. So I don't know about their prices. The best price I find for the print version on a quick net search is $81 and change, found here https://www.perfprotech.com/suzuki-s...00-96J03-01E/1 Very reasonable, in my opinion.

[jHydroman]

You might want to do on line search for a Suzuki Service Manual, I found one on line that I down loaded for free for my DF 140. This was after I purchased a hard copy from Browns Point.

JIm

[SLW2018]

Thanks guys. I was able to locate the sub battery cable and moved it to a direct connection to my battery(+) terminal. My only question is, how is this supposed to help? When I located the wire it was on the switched side of my battery switch(I'm pretty sure I put it there a year ago when I was doing some "house-keeping" chores with my battery wiring). I assumed it would be OK to put it there since I have a simple on/off battery switch so I can disconnect everything when I finish with the boat for the day. First thing I do before taking it out is turn the switch on cause I have to so I can trim the motor up for trailering. Wouldn't this have voltage supplied to the ECM relay when I crank the motor or could it be a flaky battery switch??? The battery is strong(17v if my VOM is correct) when I measured it after moving the WW. I have never noticed any power issues but I'm pretty sure Harper nailed it. Reason so is one of the symptoms I forgot to mention but Harper did was having to power-up my chart/plotter each time after starting the engine. All the other symptoms are pretty much a combination of the ones I've read on this forum. I didn't get a chance to try it out since I moved the WW but hope to this week. I appreciate all the help and insight! Thanks Harper and jHydroman, I will look into the service manuals also.

[Harper]

If I understand what you're saying, your chartplotter is on, then when you start the motor, it causes the chartplotter to turn off. If that's the case, then it sounds like the voltage drop on start is your problem. Checking battery condition in a static no-load state with a volt meter is not a good indicator of battery charge or condition. A valid check would be under load, i.e. during the cranking of the motor (or a battery tester that checks it under load). If your voltage drops too low while starting the motor, you will experience the problems that you have observed. Again, the voltage drop may not be the battery itself, but a fault in the wiring integrity.

[SLW2018]

Thanks Harper. I plan on trying it out tomorrow and I will load test the battery today before hooking up the boat. If I do find a battery issue, is it OK to hook the WW back up the way I had it(on the switched side of the batter switch)?

[Harper]

Yes, I think you were fine the way it was hooked up.

[cprice11]

One of my DF 150"s done the same thing. I moved the white wire to the always hot side of the battery switch And the rev up and die problem was fixed. The other motor runs fine with the wire on the side that can be turned off.

[BaffinBay]

Harper and others: thank you for your thoughts on this issue.

My fishing buddy had the exact same issue on his 2015 Tiburon XS22 with Suzuki DF175 engine. Short story, issue solved by relocating the sub battery cable from the "common" side of the Perko battery selector switch to the + side of the primary starting battery, and/or repairing a faulty crimp connection at the # 2 battery to Perko selector switch.

This was after hours of troubleshooting batteries (terminal voltage each battery, continuity all battery cables and cranking voltage, top off electrolyte level in all batteries, charge overnight, check specific gravity of each cell of the three batteries with refractometer), clean all battery connections on batteries and the Perko switch including ground bus, checking 15 amp fuse and continuity of the sub battery cable, clean sub battery terminal connections...)

In the midst of this the #6 battery cable from battery 2 pulled out of the #6 crimp on connector at the Perko switch BAT 2 terminal as I was moving the Perko switch. I installed a new crimp on connector using the appropriate heavy duty crimper. This issue did not appear until late in the process - no signs of heat damage, and no issue at all cranking the engine on BAT 2 on the Perko switch. This start and die issue was intermittent, and had been around for about a year, i.e. something changed.

I did not go back and put the sub battery cable on the Perko common terminal. That will have to wait for the next event. Note the start and die issue appeared with the Perko selector on BAT1 or BAT 2, and BOTH. The batteries are set up to power both the engine start circuit and the 24 V troll motor: (3) 12V batteries. BAT 1 is (2) batteries series/parallel with 12V feed to Perko switch and non switched 24V feed to the troll motor, and BAT 2 is a single 12V battery to the Perko switch BAT1.

FYI I recommend owning the Suzuki factory service manual available to owners: 99500-96J10-01E. It is a solid resource.

Regards,
Ray

[BaffinBay]

Correction: should read, "and Bat 2 is a single battery to the Perko switch BAT 2".

[Northriver08]

Mine (2008 DF 175) is doing kind of the same thing.....

On a cold start.......... after cranking it.. it will rev up and then immediately die....

ON the second attempt with no extra throttle I will crank it and it starts up then idles fine.....

On a cold start i can give it some extra throttle, crank it and it starts fine and then idles fine....

When its warm it starts perfect and idles perfect.. its just the initial cold start procedure.

[Harper]

Cold start would be after battery also sat for awhile, while warm start would have a more fully charged battery from recent engine run. My initial thought is that your battery needs to be checked. It's not fully charged or is starting to fail. How old is the battery? Also try a battery charger while the boat sits for a while. My boat's two batteries are always hooked to an onboard charger to keep them maintained while parked on the trailer. Keeps them at peak voltage.

[Northriver08]

Cold start would be after battery also sat for awhile, while warm start would have a more fully charged battery from recent engine run. My initial thought is that your battery needs to be checked. It's not fully charged or is starting to fail. How old is the battery? Also try a battery charger while the boat sits for a while. My boat's two batteries are always hooked to an onboard charger to keep them maintained while parked on the trailer. Keeps them at peak voltage.

The Batteries are only 2 seasons old... and i keep them on a Noco Genius charger/maintainer in the garage all year long.....

This is a new issue this season....