This is a real head scratcher...tried lots of troubleshooting including taking to dealer for 2 weeks. Battery on 2002 4Runner goes dead after about 4 days of not driving. Replaced battery. Measured current drain in-line battery terminal...about 20-40 mA. Car runs great and no problems or warning lights. Tried several times to catch the issue by keeping multimeter in-line and check current drain periodically, but can't catch it. Seems to be intermittent problem. Dealer tried same, could not figure it out. Previous owner put a brake controller on it for towing, I removed all connections to the battery thinking that was the issue, but still have battery going dead after about 4 days of not driving.
Some hints that may or may not be related:
-once on starting up car, lots of warning lights came on, accelerator hard to push, no power steering. Shut off and started up again, everything fine.
-once when charging battery, noticed humming sound in TRC MTR relay, and in throttle body. Removed TRC MTR relay, disconnected accelerator pedal position sensor, and sounds went away. Reconnected, sounds came back. Decided to disconnect and let battery charge overnight. Reconnected after battery fully charged, no sound, car starts and runs fine. Dealer also noticed this noise, and recommended I replace the throttle body. I said prove that is what causes battery to drain and I will, they could not prove anything.
Sorry for long post. I am somewhat experienced with cars and elex...EE background. Any ideas? I was thinking it could be the ECM since it doesn't seem like there should ever be a condition when the TRC MTR relay is operating with the ignition switch off, likewise anything on throttle body operating with ignition switch off.
Some hints that may or may not be related:
-once on starting up car, lots of warning lights came on, accelerator hard to push, no power steering. Shut off and started up again, everything fine.
-once when charging battery, noticed humming sound in TRC MTR relay, and in throttle body. Removed TRC MTR relay, disconnected accelerator pedal position sensor, and sounds went away. Reconnected, sounds came back. Decided to disconnect and let battery charge overnight. Reconnected after battery fully charged, no sound, car starts and runs fine. Dealer also noticed this noise, and recommended I replace the throttle body. I said prove that is what causes battery to drain and I will, they could not prove anything.
Sorry for long post. I am somewhat experienced with cars and elex...EE background. Any ideas? I was thinking it could be the ECM since it doesn't seem like there should ever be a condition when the TRC MTR relay is operating with the ignition switch off, likewise anything on throttle body operating with ignition switch off.
