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Has anyone disconnected the 12v battery to check what the battery draw is? I experience occasional dead battery situations. Putting the charger on for only a few minutes gets it to start. Of course I have to punch in the secret code to gate audio/nav working again. I tried this and measured about 250 mA with everything turned off. Is this normal? I don't want to give the dealer a blank check to for a witch hunt. It could well be COVID lack of activity. I'm giving the CR-Z to a niece but would like to have everything working first.
TIA
Don
 

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Discussion Starter #3
Someone else or an older thread may have the answer to your question about the draw, but my question is have you tested your 12 volt battery lately? Inactivity/short trips kills them pretty quick.
A few months ago I had a failure of the cooling fan for the electronics, one symptom of which is a failure of the HV battery to charge the 12V. Before I came to that conclusion I guessed that it might be a failure of the 12V battery, so I bought a new one. That didn't fix it so I honed in on the cooling fan issue. Now I'm wondering how/if the HV battery keeps the 12V charged even when the car is "off".
 

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Now I'm wondering how/if the HV battery keeps the 12V charged even when the car is "off".
No it doesn't.
The IMA battery is completely isolated and inert when the car is off.

Parasitic 12V drain can come from a multitude of circuits.
Bad alarms, bad lights, mods, etc etc.

To narrow it down put the meter where you can see it and then start pulling fuses one at a time and watching the drain.

A bad courtesy light door/boot switch can do it.
They start passing some current which is insufficient to make the filament in the bulb glow but drains the battery. :(
 

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Discussion Starter #5
No it doesn't.
The IMA battery is completely isolated and inert when the car is off.

Parasitic 12V drain can come from a multitude of circuits.
Bad alarms, bad lights, mods, etc etc.

To narrow it down put the meter where you can see it and then start pulling fuses one at a time and watching the drain.

A bad courtesy light door/boot switch can do it.
They start passing some current which is insufficient to make the filament in the bulb glow but drains the battery. :(
Now that you mention it, I recall a battery rundown because a map light was left on and they are just simple always active switches. Since I don't drive much at night, I might not notice. This has happened often enough that I keep the secret code written in a secret place.
 

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Move the over head switch from door to off and always make sure the Map lights are indeed off. Turn off the auto headlights. A common failure is the alarm switch for the hood which makes the alarm go off and eventually drains the under hood battery. If your car is parked where you will not hear our feeble horn but come back to a no start. Other failures that cause the battery to be drained will sometimes cause the alarm to go off which will then drain the battery.

We have other recent postings Seems to be electrical but don't know where to start & Parasitic Battery Drain 2013 CRZ with a similar draining issue but it is more constant and they have disconnected the door locks and have done other things and cannot find the drain. Another member in one of those postings found a defective blue tooth module. Doing as @PeterPerkins recommends is the right way to find what circuit is causing the drain or how big it is.
 

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Discussion Starter #7
Move the over head switch from door to off and always make sure the Map lights are indeed off. Turn off the auto headlights. A common failure is the alarm switch for the hood which makes the alarm go off and eventually drains the under hood battery. If your car is parked where you will not hear our feeble horn but come back to a no start. Other failures that cause the battery to be drained will sometimes cause the alarm to go off which will then drain the battery.

We have other recent postings Seems to be electrical but don't know where to start & Parasitic Battery Drain 2013 CRZ with a similar draining issue but it is more constant and they have disconnected the door locks and have done other things and cannot find the drain. Another member in one of those postings found a defective blue tooth module. Doing as @PeterPerkins recommends is the right way to find what circuit is causing the drain or how big it is.
Have to (find and) check the hood switch. In recent months the alarm has gone off for no apparent reason. But I hear it because I added an airhorn. What can trigger the alarm? Side, rear door and hood switches, plus the panic button on the fob? I recently swapped fobs and haven't had the alarm go off again. Maybe a new fob battery.
 

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The switch is part of the hood latch and is the only wire near the latch at the front of the car easier to feel it than see it. There are many postings on this switch. If you unplug it make sure you put some electrical tape over the connector so it does not corrode. If the battery voltage drops below a certain point the alarm will go off, kind of a Viscous circle to make sure the under hood battery is dead.

I have an odd habit, I replace my Fob batteries every year on my birthday even for the Key I never use. Alarm is triggered by opening the door or the hood, Panic switch and maybe the hatch but not sure on that.

I hope your air horn is on a relay fed by a different circuit other than the horn circuit. You may even want the air horn on a circuit that is not live when car is off unless you specifically want to hear it when the alarm is triggered.

Have to (find and) check the hood switch. In recent months the alarm has gone off for no apparent reason. But I hear it because I added an airhorn. What can trigger the alarm? Side, rear door and hood switches, plus the panic button on the fob? I recently swapped fobs and haven't had the alarm go off again. Maybe a new fob battery.
 

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100 mA or less is where you want to be, really.
 

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Discussion Starter #10
The switch is part of the hood latch and is the only wire near the latch at the front of the car easier to feel it than see it. There are many postings on this switch. If you unplug it make sure you put some electrical tape over the connector so it does not corrode. If the battery voltage drops below a certain point the alarm will go off, kind of a Viscous circle to make sure the under hood battery is dead.

I have an odd habit, I replace my Fob batteries every year on my birthday even for the Key I never use. Alarm is triggered by opening the door or the hood, Panic switch and maybe the hatch but not sure on that.

I hope your air horn is on a relay fed by a different circuit other than the horn circuit. You may even want the air horn on a circuit that is not live when car is off unless you specifically want to hear it when the alarm is triggered.
Thanks, I'll look for it. Yes, the airhorn was on a separate relay, fused directly from the battery. Removed it the other day in prep for giving it to niece, before I pick up my new Mach-e on Tuesday.
 

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Discussion Starter #11
Put meter in circuit again today in anticipation of sleuthing. This time closed the hood! Draw was about 1/4 amp, but after a few minutes, dropped to 14ma. That's pretty good. Guess it was just related to pandemic lack of use. Story closed. Thanks to all for the help.
 

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Was just away to say, The day I got my CRZ home the alarm was going off at stupid A.M. due to the hood latch. It had been draining the power aswell so just pulled the plug and its been fine ever since.
 
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