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the usual suspects, glove box and trunk light, power antenna check out ok. Splitting the ckt at C206 yields mixed results. My meter bounces between 100 and 200 MA. Ran out of patience, so I'll leave further investigation for another time. This is in the Grape, which has sat since Xmas. What is considered acceptable drain, keeping various memory chips alive? Thought I 'd fixed this trouble. . Discovered interesting factoid, low oil level has a memory according to the ETM for my 88. This has been getting flaky. A low oil level warning can be fixed by beating on the check panel.

Acceptable resting milliamp draw (ign off) is 20-25 milliamps at the upper end.

Disconnect the Alternator and see what you get. A failed diode can generate a pull like you have.

Dick

I had a pull like that -- Turned out being the power attenna. It "seemed" ok -- but there was a wiring grounding somewhere. I had my dad sit in the front looking at the voltage while I started disconnecting things. When I disconnected the power attenna -- the battery voltage jumped by about .05 volts!
That darn attenna would make a dead car overnight.


[Edit by Tjn182 on [TIME]1107877566[/TIME]]

Part deux, traced draw as far as the interior light timer. Thought I had it, but the relay from my parts causes the same drain. 200 MA. gotta be something on that branch causing it. Called on account of cold and dark. More tomorrow

The interior light switch is a circuit board attached to the driver's door handle front hinge (IIRC) and has a small (less than " x ") metal flap on one side that when it touches ground, it activates the circuit for the interior lights delay and the lock heater. I don't know if this can cause the problem you have.

Originally posted by Techboy
Acceptable resting milliamp draw (ign off) is 20-25 milliamps at the upper end.

My '87 535is has a 60mA draw through fuse 5. I think that's due to the stock radio.

Heh, heh . My face is kinda red. yes BS, when the door button is pushed in the draw goes down to a more acceptable 40 MA. But could somebody "splain to me why when the interior light rocker switch is in the off position, why there is a 170 MA draw if a door is open? Disco'ing the lock htr has no effect . BTW, BS, were you known as Keith F in a former incarnation? Thanks Ron, then the 40MA draw, is prolly acceptable. The Grape has a RS radio/cassette

Originally posted by a
...could somebody "splain to me why when the interior light rocker switch is in the off position, why there is a 170 MA draw if a door is open?

The interior light timer control (a relay with a delay circuit) is activated regardless of the rocker switch position. When activated, the unit's internal relay is turned on, and its coil draws current until the relay turns off. If you close the door and listen, you can hear the unit turn off after several seconds. It's under the dash, up against the firewall, among all that other stuff above the pedals.

Here's a link to a PDF schematic of one version of the light delay unit.

The circuit is designed so that once it shuts off, it stops drawing current. The TG and TK pins are momentarily grounded by the door handle and door jamb switches, respectively. That leaves pin 31 as the ground for the circuit while it's timing out. Once it times out and the relay opens, there's no path to pin 31, i.e. no current draw.

[Edited 8/24/2008 to enable BBCode]

Thanks , Ron. I was hoping you would see this