Hello, new forum user here. I have a 2003 Grand Caravan with a battery drain issue. Battery drains overnight, researched the issue and did a drain test via the negative cable with a multimeter; shows 1.34 Amp drain! Disconnecting the HZD LP fuse drops it to about 0.65 Amps. Removing the IOD fuse drops it to 0.1 Amp (Regardless of whether the hzd fuse in in or out.). No effect with any other fuses/relays.

Have been led to believe this indicates problem is in the dash: most likely the instrument panel. A bulb in the dash has blown, but that occurred AFTER the drain issue started.

Any suggestions on where to search next? I don't look forward to opening the panel... but if I must I will. How do I isolate the drain further?

Thanks for any response!

 

You've got a pretty hefty drain. Max should be around 30 milliamps, that's .030 amps so you're over by more than 1000%. Are you letting it sleep before taking a measurement, meaning let it sit 15 minutes once you have the meter connected?

 

Thanks for the quick reply! I let the vehicle sit 20 minutes before taking the measurement, so I'm unfortunately certain that's what's happening. The battery can go completely dead overnight.

 

AH HA! Got it!

You meant to connect the multimeter (in series between battery negative post and cable) and THEN wait 20 minutes with the multimeter still attached and running! I waited and then connected the meter, which interrupted the circuit and initiated a system restart... hence 1.35 amps.

/HEADDESK!/

Did it the correct way and got... 0.53 amps. still WAY too high, but now when I pulled the fuses (with meter still attached, something I was taught not to do) I found the culprit. My power lift gate. Damn thing has always been problematic. Pull the relay fuse and it drops to 0.02 Amps (20milli amps, much happier!).

Thank you sir, you are a real benefit to this board!

 

Great news. It's rare when someone posts the results of troubleshooting with this test. Thanks for passing it on.

Looking at the wiring diagram it looks like there's two motors and a controller. One motor to power the door up and down and another to pull it in and cinch it closed. The controller controls both. The motors have switches, a clutch, and sensors that might be fixable. Looks like you're not quite done yet.