Alternator?

[M3powerzz]

I didn't drive the car for a week, came back to a dead battery, I replaced the battery about 3 weeks prior. Check charging system thru the hidden menu, and see 14.0v at start up. Then it drops to 13.7v-13.8v ,at idle and driving. Is that the normal range or should it be 14.0v and up?

[nahvkolaj]

13.7V is nominal I believe. Sounds like a parasitic drain.

[M3powerzz]

Ok thanks, I will have to check that out. Close doors and wait for the car to go to sleep, Do I have to hit the lock button?

[bigjae46]

Depending on where you measure it...but 13.7 from the DME is within range.

[sapote]

I didn't drive the car for a week, came back to a dead battery,

How do you determine it's a dead batt?
Hidden dispay shows 13.7v is good, but the DME gets the 13.7v before the batt post, so the batt may have less than 13.7v of the cable was not tight on the post and didn't charge it properly.
So when the engine running, measure directly at the batt two posts.

[M3powerzz]

I took the battery to get tested and it wasn't holding charge.
I will test the voltage today at the battery posts.

[Zack]

Let us know how it goes. If the battery isn't getting 13.6-14+ volts you will need to check voltage drop of the battery cables. Test from the positive post to the alternator output post, DVOM on DC V. Expect to see very little voltage <.5 v. Then do the same from battery negative to chassis ground and expect similar results. If either cable shows more voltage drop replace cable/clean connections etc.

[sapote]

Let us know how it goes. If the battery isn't getting 13.6-14+ volts you will need to check voltage drop of the battery cables. Test from the positive post to the alternator output post, DVOM on DC V. Expect to see very little voltage <.5 v. Then do the same from battery negative to chassis ground and expect similar results. If either cable shows more voltage drop replace cable/clean connections etc.

The total cable voltage drop should be measured this way:
engine idling, measure alternator output post to the body, then compare to the measurement at battery posts.

[M3powerzz]

I check the voltage from the alternator to body, it was 14.2v, also checked the positive post in front passenger side of engine , 14.1v. Then I checked the battery post is 13.9-14.0v. Put a amp clamp on negative cable by battery, when car is shut off is .031 amps.. after 15 mins it went down too .003 amps.

[sapote]

I check the voltage from the alternator to body, it was 14.2v, also checked the positive post in front passenger side of engine , 14.1v. Then I checked the battery post is 13.9-14.0v. Put an amp clamp on negative cable by battery, when car is shut off is .031 amps.. after 15 mins it went down too .003 amps.

The data are perfectly fine.

[Zack]

All of that looks pretty good to me. Max allowable amperage draw is somewhere around milliamps. you are sitting at 30. This doesn't mean you don't have a module waking up randomly causing a draw that is intermittent.

[M3powerzz]

Does the clown nose , use alot of amps, will it kill a battery within a week? Also it was very cold where I live.

[sapote]

Does the clown nose , use alot of amps, will it kill a battery within a week? Also it was very cold where I live.

A flow frequency flashing LED shouldn't use much current.

[sapote]

you are sitting at 30. .

He said it slept at 3mA, not 30.
3mA is very low.

[Shonky]

3mA I'd actually say is actually too low so I wouldn't necessarily trust that reading.

Also doesn't mean something isn't waking up later on and running the battery down.

Spec is less than 40mA

Mine measured at 19mA