Echo parasitic load problem

[wasafiri]

I have a 2002 Echo, it has been having a mysterious battery drain. (battery will drain in 4-5hrs when car turned off. I note that the battery is not the problem here.) I purchased a light tester, hooked it up and started pulling fuses one by one to isolate the circuit that was draining the battery.

As soon as I pulled the 15A Dome fuse, the bulb went out. (I should note that the bulb hadn't been dim... it had been rather BRIGHT, and as soon as i pulled that fuse, the light went completely out...)

So I have isolated the specific circuit... but have not been able to isolate where on that circuit the leak is coming from... I have disconnected the dome light, the trunk light, the radio, the clock and none of these things is the culprit...

Toyota wants to charge me $250 just to diagnose, do any of you have suggestions as to what the leak may be and where I should look?

Thanks in advance...

[toyomoho]

Items on the Dome fuse: clock, combination meter, headlight, interior light, key/seat belt/ light reminders, radio/player, theft deterrent and wireless door lock control systems.

[wasafiri]

That leaves the combination meter... how do I check to see if the combination meter is the source of the leak?

[wasafiri]

Alright, seems I left a light on while doing the previous testing, so I redid it.

This time, I unplugged the radio and now the test light is completely dark when I test the continuity. Before, the light was sort of pulsing... not a constant light, but a pulsing light, odd, right? But now, completely dark.

I measured the draw on the battery... at the 20mA setting on the millimeter, it shows .22 draw... is that within normal parameters?

[toyomoho]

1 amp equals 1000 ma. 20 ma is not a lot of current and it would seem strange if this alone would drain the battery in 4-5 hours. The battery is likely rated for say 40 A/H, meaning it can supply 40 amps for one hour. Or fewer amps if spread out over many hours.

Not sure what a pulsing current would result from with the radio, any type of security system having a blinking light? Might be the LED's in the clock if they are on.

Are you sure it is not the battery, have you removed the battery cable and let the car sit to see if the battery goes dead? Perhaps the alternator is not charging the battery fully. There should be about 13-14.5v at the battery when the engine is running. When engine off, a battery with a 100% charge has a voltage reading of about 12.8v.

There may be a recall on this car for the crank sensor. If for some reason everything electrical just shuts down when driving, this could be the problem.

[wasafiri]

Toyomoho, thanks for your help. This was happening with the stock battery, so I suspected it was the problem and replaced it with an Autocraft Titanium 640CCA battery. Problem persists.

So a reading of .22 on the 20mA multimeter setting means 22 milliamps? For some reason I thought it meant 222 milliamps. But that's good, because anything over 50 milliamps is excessive, right?

Anyway, my battery hasn't died since I disconnected the radio...but the battery does seem to be draining more than I like. This morning, after the car sat for ~14hr, the battery was at 12.67v (it was 12.82v with engine off, so .15v deprecation in 14hr)

[toyomoho]

To read the meter, take the reading and multiply it by the scale setting. 0.22 times 20ma equals 4.4ma. Be sure you have the meter set property. Most meters require one probe plug to be moved to the Amp or Ma socket of the meter to read amps.

So, the meter would have one probe (red/positive) plugged into the V/ohm socket The other (black/negative) would be moved to the Amp or Ma socket.

Check you meter as it may be different then the above setups.

There also could be 20ma/10A meter setting. This means the meter will read down to 20ma when the probe is plugged into the ma socket and up to 10A when plugged into the 10A socket.

I state this because if the battery is still loosing charge (and is new), it must be loosing it through the cables. The meter has to pickup this current flow.

Check the link below for battery voltage versus percentage charge of battery.

http://en.wikipedia.org/wiki/Car_battery

The voltages are a little lower then I stated but you will see the difference between fully charged and 0% charge is not that large.

Don't let the battery go completely dead as this will shorten its life. If it keeps dropping start the car and recharge it..