Featured Dome light fuse / J6 Connector / slow battery drain

20191231_154719 by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

Hello to all.
I'm new here, first post. Been reading blogs for a long time. I hope someone smarter than me can help.
I have a 2007 Prius hatchback gen 3
The dam car keeps dying the battery in the winter, I even attached two batteries in series for the last winter, but now I decided to solve the problem.
I traced the problem to a dome fuse and from there to a J6 connector that have issues.
The problem is that the J6 connector connects to 34 subsystems, and I do not have the expertise or time to take everything apart.

I found that those 3 connectors on the picture 1 are grounded and I have no idea where they go to.

Screenshot_20191231-151958_Adobe Acrobat by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

Screenshot_20191231-143020_Adobe Acrobat by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

Here are the one grounded

20191231_154719 by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

Here is a back picture

20191231_154546 by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

20191231_154536 by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

Here is the manual description, it only says j6, does not describe what each one do

Screenshot_20191231-151958_Adobe Acrobat by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

Any help is appreciated

 

I'm sure it is the J6, because disconnecting it, the draw falls from 0.38A to 0.05A, and there is a red wire that is grounded.

 

Battery is 6 months old and the other is 3 months, a yellowtop. I drive about 100 Mike's per week, sometimes 350 a week. The car makes about 44.5 mph.
I tested the charging on the battery and says 13.7 stable.
I already tested everything else and found that connection is the culprit. It drains a stable 0.30A alone. Removing the fuse it reduces that much, to almost Zero. Removing the Cap from the J6 does the same.
Testing the leads on the J6 shows 3 grounds.

20191231_154719 by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

If only I knew what these points are would be easier.

Screenshot_20191231-151958_Adobe Acrobat by MozartFixerPrius posted Dec 31, 2019 at 4:04 PM

Wiring diagram

 

It is a pain to test that information, it doesn't loose enough to shut down the bat low voltage, since 0.38A or 0.4A isn't that much, but in two days does drop to 11.5V. the battery is small on Prius.

I can calculate and estimate, 0.4A/hr * 20h = 8A, and 8A at 12v is about 96watts. But constant drop can cause battery problems, like loosing acidity.

Anyways, treating the battery doesn't solve the problem. The solution is to find the parasitic draw, and i found where the parasitic drain is occuring, I am just not sure where it leads.

 

thanks elektroingenieur

I have reviewed all the answers on this forum prior to open my own blog, the decision was not lightly or lasy. Like I said I before, I tested the continuity in all the terminals and found that the terminals above mentioned are grounded to the chassis, I didn't test the resistance, perhaps I should, or I WILL and will give a response here. , meaning they are bad. If all BBB is supposed to be shorted so they are connected without a splice then one of them is shorted, and so forth.

It is good to know that most of it are due to the combination meter. I will have to take the whole front panels to access the plug for that, so I can test.

Test conditions are the same as any other electrical test.
1. Doors open / close
2. lights on / off
3. test the amperage every time with a boy helper
4. wait for the car to settle with all locked and amperemeter outside

what did I find?
1. normally I will have a 0.4 A draw constant with the key away from the car and the keyless system off
2. removing fuse dome will reduce to 0.08A draw (acceptable?) maybe
3. testing the J6 connector shows one of the red leads BBB is shorted to ground showing continuity or very low resistance (to be tested the resistance)
4. I did not follow any circuit after the J6 so I cannot say what is beyond causing the issue, I guess I have to take the panel apart to find the issue.

 

I found the issue, couldn't sleep after posting the tread.
It is the combination cluster. I took apart the panel to that point, disconnected one of the white connectors for the cluster and the draw came down from 0.38 to 0.05A instantly.
Now I removed the whole panel off, and I am studying what can I do to fix it or replace it.

 

20200101_140611 by MozartFixerPrius posted Jan 1, 2020 at 2:08 PM

I have the cluster out. Checked some capacitors and most are way off. I will recheck or maybe try to change the whole thingy.

 

Hi thanks, I will get in touch with the repair man that I hire didn't work it right. Unfortunately, I already paid to be fixed. Hope will work.

Thanks for all so far, has been a great adventure.

I will follow up.

Texas hybrid battery, thanks for the info.