Battery issues

[tmonty80]

Hey folks. I have an 02 ES300 and have a battery drainage issue. The battery is a couple of months old and if I let it sit for 4 or 5 days it's dies and I have to charge it up. Alternator has been replaced and is charging just fine. I conducted a parasitic draw test and there was nothing drawing amps. When the car is running with the AC off, the light for the recirculating air blinks and with he AC on the light for the AC and recirculating air both blink, but the air blows very cold. 

Has anyone had any issues or can point me in the right direction to find what is draining my battery? It's intermittent like a relay randomly gets stuck or something. Would a sticky key fob button drain the battery?

 

Thank you

[RX400h]

Quote

Some of these will not be applicable, but see below for some possible causes and solutions based on the information I found:

Battery Drainage:

• One possible cause of battery drain in Lexus vehicles is the multiplex body control module. This module can cause a parasitic drain if it’s malfunctioning.
• Another user reported a similar issue where their car battery would drain after several days of not being driven. They found that the parasitic load was over 30mA at all times. If the load is much higher than 30mA, it could indicate that something is remaining powered up and causing the drain.
• It’s also possible that the Network Gateway Computer is not properly going into sleep mode when the car is turned off. This can result in excessive parasitic draw and a discharged battery condition.

Blinking AC and Recirculating Air Lights:

• The blinking AC light could be due to a bad A/C magnetic clutch relay in the fuse box under the hood. Replacing this relay with an updated one has reportedly fixed the issue for some Lexus owners.
• You can also try entering the diagnostic mode of your car’s climate control system to check for any error codes. To do this, with the ignition OFF, press and hold the Auto button and the Recirc button at the same time, then turn the key to ON⁷.

Key Fob:

• A key fob can cause a slight drain on the battery as it constantly tries to communicate with the car. However, this generally won’t completely drain a healthy car battery. If you think your key fob is draining your car’s battery, it’s likely time to get a new battery.

Please note that these are just possible causes and solutions. It’s always best to consult with an auto-electric shop for nagging battery drains.