Battery draining even while riding

[Garyg99]

I have a 2008 gti that recently had new ecu installed took it for first ride of the year and battery drained in like 45 min while riding to point wouldn’t start. After recharging battery noticed that gauge cluster comes on every 15 seconds or so like I just plugged in key and then goes off again and notice it was clicking a relay in front compartment possibly starter relay and there’s a humming from the engine area for a second or 2 like the fuel pump is priming. If I unplug the 2 wire plug from the Dess it stops doing it. Just wondering if it’s possible something is wrong with new ecu or maybe the Dess post? Ski runs and drives fine till battery dies. Thanks for any help in advance these are my first pwc’s so I’m a newb at all this.

 

[MacSeaDoo]

If your battery dies while driving you have a charging issue.

The DESS post issue may be related and it may not.

Here is what I would do:

1.. Are your battery terminals tight and free of corrosion?
2.. When running, put a multimeter on the battery. You should get 14v. If you don't, you have a charging problem. That could be a ground problem, stator/rectifier issue.
3.. Are your grounds tight and free if corrosion? There are 3 of them located at the front of the block below where you add oil.

As for the DESS. There is a magnetic reed switch in the post. When you put the key in it activates telling the ecu to light up the guage asssy and prime the fuel pump. If that is happening with no key in the post, the most might be bad.

Why did you replace the original ECU?

 

[Garyg99]

Thanks, gives me some things to try. bought a new ecu bc of a different battery problem, was told it would fix it and I think it did but then all this started. I’m just hoping not going to have to buy a wiring harness after dropping 700 on a ecu.

 

[MacSeaDoo]

What was the differnt battery problem? Just curious as it all may be related.

 

[Garyg99]

What was the differnt battery problem? Just curious as it all may be related.

There’s was something humming around the motor area.( almost like the fuel pump but not quite?)and causing it to kill battery over night. Mechanic said it was a short in ecu. Im hoping it’s not related otherwise I wasted 700 on ecu and can’t trust my mechanic next time.lol. The battery I have is 11 mo. old. But tested bad so got new battery and ordered new dess post. Haven’t had time to look at grounds yet but will this week. And then I’ll look into rectifier and stator if it still persist.

 

[Mr@RXT]

If your battery dies while driving you have a charging issue.

The DESS post issue may be related and it may not.

Here is what I would do:

1.. Are your battery terminals tight and free of corrosion?
2.. When running, put a multimeter on the battery. You should get 14v. If you don't, you have a charging problem. That could be a ground problem, stator/rectifier issue.
3.. Are your grounds tight and free if corrosion? There are 3 of them located at the front of the block below where you add oil.

As for the DESS. There is a magnetic reed switch in the post. When you put the key in it activates telling the ecu to light up the guage asssy and prime the fuel pump. If that is happening with no key in the post, the most might be bad.

Why did you replace the original ECU?

Hell my ÉCU is all messed up but everything works fine if the ÉCU goes & everything else is fine leave it

 

[Garyg99]

a well I would probably just patch it usually but this is the wife’s ski and she goes out sometimes by herself when we’re at the lake so just like it to be right on that one. Lol

 

[Garyg99]

FYI put new dess on it stopped the clicking, fuel pump and dash random power ups without key in it. Grounds seem ok will be checking it out as far as battery drain this weekend.

 

[Garyg99]

Ok dess post fixed some of the issues but still after about an hour of riding dead battery. Checked three of the grounds all good to go. Battery terminals are tight no corrosion. Put it in the water checked battery read 12.8 volts with it running read 13.68 ish? Ordered a rectifier just bc easiest thing to replace next. So is 13.68 volts enough or should it be reading a full 14 volts? Thanks for the help so far!

 

[only1battman]

I have an 08 RXT and am weary of the charging system, so installed a secondary volt meter that just reads battery voltage. basically at any speed after about 2 minutes of engine running the battery is at least 14v.
This article from Partzilla is what i used to diagnose when i had a bad rectifier/regulator.
www.partzilla.com
you can also use the video at the bottom to check the AC voltage output from the stator. if the stator starts to go, it will start to put out less voltage than required, basically not charging the battery fast enough to keep up.

 

[skiasylum]

I have an 08 RXT and am weary of the charging system, so installed a secondary volt meter that just reads battery voltage. basically at any speed after about 2 minutes of engine running the battery is at least 14v.
This article from Partzilla is what i used to diagnose when i had a bad rectifier/regulator.
www.partzilla.com
you can also use the video at the bottom to check the AC voltage output from the stator. if the stator starts to go, it will start to put out less voltage than required, basically not charging the battery fast enough to keep up.

Your charging system is within limits. You might have another bad battery.