DaimlerChrysler LH New Yorker 1994, Электронное руководство по обслуживанию

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IGNITION OFF DRAW (IOD)
GENERAL INFORMATION
A completely normal vehicle will have a small
amount of current drain on the battery with the key
out of the ignition. It can range from 15 to 25 milli-
amperes after all the modules time out. If a vehicle
will not be operated for approximately a month, the
MAIN Feed Connector should be opened to eliminate
the vehicle electrical drain on the battery. The Main
Feed Connector is between the battery and the power
distribution center (Fig. 19).
IGNITION OFF DRAW (IOD) TESTS
High current draw on the battery with the ignition
OFF will discharge a battery. After a dead battery is
serviced the vehicle ignition off draw (IOD) should be
checked. Determine if a high current draw condition
exists first check the vehicle with a test light.
(1) Verify that all electrical accessories are OFF.
•
Remove key from ignition switch
•
Turn off all lights
•
Trunk lid and glove box door is closed
•
Sun visor vanity lights are OFF
•
All doors are closed
•
Allow the Illuminated Entry System to time out in
approximately 30 seconds, if equipped.
(2) Disconnect battery negative cable (Fig. 15).
(3) Connect a 12-volt test light, with a cold resis-
tance of 5-7 ohms, between the negative cable clamp
and the battery negative post (Fig. 19). The test light
will remain lit for approximately a minute and then
go out.
Each time the test light or milliamp meter is dis-
connected and connected, all electronic timer func-
tions will be activated for approximately one minute.
BULB LIGHTS AND STAYS ON
There is either a short circuit or a fault in an
electronic module. Two fuses in the power distribution
center feed the electronic control modules with igni-
tion off draw.
•
Interior/brake lamp fuse J (20 Amp)
•
Powertrain control fuse A (20 Amp)
(1) Remove both fuses (A and J). By removing these
fuses all ignition off draw from the electronic control
modules will be disconnected. The test light should go
out. If test light goes out go to step 2. If test light does
not go out there is a short circuit. Refer to Group 8W,
Wiring Diagrams.
(2) Install the powertrain and transmission control
modules fuse A. If test light lites, there is a short
circuit or faultily powertrain/transmission control
module.
(a) Disconnect powertrain control module.
(b) If test light goes out, replace powertrain con-
trol module.
(c) If light does not go out, disconnect the trans-
mission control module.
(d) If test light goes out, replace transmission
control module.
(e) If test light does not go out, there is a short
circuit to one of the modules. Refer to Group 8W,
Wiring Diagrams.
(3) Install the interior/brake lamp fuse J. If test
light lites, go to the junction block and remove two
fuses #4 and #13.
•
Stop lamp fuse #4 (20 amp)
•
Interior lighting fuse #13 (10 amp)
(4) If test light goes out, go to step 5. If the test
light stays on, there is a short circuit in the wiring
between the power distribution center and the junc-
tion block. Refer to Group 8W, wiring diagrams.
(5) Install the stop lamp fuse #4. If test light lites,
there is a short circuit between the fuse and the stop
lamps. Refer to Group 8W, Wiring Diagrams. If test
light does not lite, go to step 6.
(6) Install the interior lighting fuse #13. Close all
doors. If test light lites, there is a short circuit or a
faulty:
•
Radio
•
Body controller
•
Remote keyless entry module
(7) Disconnect the three components. If test light
goes out, go to step 8. If test light does not go out,
with all components disconnected there is a short
circuit between the fuse and the components. Refer to
Group 8W, Wiring Diagrams. Set meter to the highest
mA range.
Fig. 19 Ignition OFF Draw (IOD) Test
BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 9