Using Voltmeter
Using Diagnostic Trouble Code Check Harness (MB991529), connect voltmeter to Data Link Connector (DLC) terminal No. 4 (ground) or No. 5 (ground) and terminal No. 9 (ETACS-ECU). See Fig 1 . Operate indicated switches. See SWITCH INPUT SIGNAL REQUIREMENTS table. If switch input signal is sent to DLC, voltmeter needle will fluctuate once. If switch input is not received at DLC, diagnose problem. See INPUT SIGNAL SYMPTOM TEST INDEX table.
SWITCH INPUT SIGNAL REQUIREMENTS
| Input Signal | Condition To Activate Input Signal | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Ignition Switch (ACC) | Turn From LOCK To ACC Position | |||||||||
| Ignition Switch (IG1) | Turn From ACC To ON Position | |||||||||
| Key Reminder Switch | Remove Ignition Key From Ignition Key Cylinder | |||||||||
| Hazard Light Switch | Turn Switch From OFF To ON Position | |||||||||
| Foglight Switch | Turn Switch From OFF To ON Position | |||||||||
| Driver's Seat Belt Switch | With Ignition Switch In ON Position, Remove Seat Belt Tongue From Belt Buckle | |||||||||
| Driver's Or Front Passenger's Door Switch | Open Appropriate Door | |||||||||
| Door Switches | Open Any Door When All Doors Are Closed | |||||||||
| Door Lock Key Cylinder Switch | Using Key, Turn Door Lock To LOCK Or UNLOCK Position | |||||||||
| Front Door Lock Actuator Switch | Move Appropriate Door Lock Knob To LOCK Or UNLOCK Position | |||||||||
| Rear Door Lock Actuator Switch (1) | Move Appropriate Door Lock Knob To LOCK Or UNLOCK Position | |||||||||
| Door Lock Switch (2) | Press LOCK Or UNLOCK Side Of Switch | |||||||||
| Hood Switch (1) | Open Hood | |||||||||
| Trunk Lid Latch Switch (1) | Open Trunk Lid | |||||||||
| Trunk Lid Lock Key Cylinder Switch (1) | Using Key, Turn Trunk Lock To UNLOCK Position | |||||||||
| Column Switch | ||||||||||
| Taillight Switch | Turn Lighting Switch From OFF to TAILLIGHT Position | |||||||||
| Headlight Switch | Turn Lighting Switch From TAILLIGHT to HEADLIGHT Position | |||||||||
| Passing Light Switch | Turn Dimmer/Passing Switch From OFF To PASSING Position | |||||||||
| Dimmer Switch | Turn Dimmer/Passing Switch From PASSING To DIMMER Position | |||||||||
| Turn Signal Switch | Turn From OFF To ON Position | |||||||||
| Wiper Mist Switch | Turn From OFF To ON Position | |||||||||
| Intermittent Wiper Switch | Turn From OFF To ON Position | |||||||||
| Low Speed Wiper Switch | Turn From OFF To ON Position | |||||||||
| High Speed Wiper Switch | Turn From OFF To ON Position | |||||||||
| Intermittent Wiper Interval Adjusting Knob | (3) | |||||||||
| Washer Switch | Turn From OFF To ON Position | |||||||||
| Transmitter (4) | ||||||||||
| LOCK Switch | Turn From OFF To ON Position | |||||||||
| UNLOCK Switch | Turn From OFF To ON Position | |||||||||
| PANIC Switch (1) | Turn From OFF To ON Position | |||||||||
|
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INPUT SIGNAL SYMPTOM TEST INDEX
| Input Signal Symptom | Perform Symptom Test | |
|---|---|---|
| Ignition Switch ACC Signal Is Not Sent | N-1 | |
| Ignition Switch IG1 Signal Is Not Sent | N-2 | |
| Key Reminder Switch Signal Is Not Sent | N-3 | |
| Hazard Warning Light Switch Signal Is Not Sent | N-4 | |
| Fog Light Switch Signal Is Not Sent | N-5 | |
| Driver's Seat Belt Switch Signal Is Not Sent | N-6 | |
| Any Or All Door Switch Signals Not Sent | N-7 | |
| Driver's Or Front Passenger's Door Lock Key Cylinder Switch Signal Is Not Sent | N-8 | |
| Any Door Lock Actuator Switch Signal Not Sent | N-9 | |
| Door Lock Switch (Incorporated In Power Window Main Switch & Power Window Sub Switch) Signal Is Not Sent | N-10 | |
| Hood Switch Signal Is Not Sent | N-11 | |
| Trunk Lid Latch Switch Signal Is Not Sent | N-12 | |
| Trunk Lid Lock Key Cylinder Switch Signal Is Not Sent | N-13 | |
| Column Switch | ||
| Taillight Switch Signal Is Not Sent | N-14 | |
| Headlight Switch Signal Is Not Sent | N-14 | |
| Passing Light Switch Signal Is Not Sent | N-14 | |
| Dimmer Switch Signal Is Not Sent | N-14 | |
| Turn Signal Light Switch Signal Is Not Sent | N-14 | |
| Windshield Mist Wiper Switch Signal Is Not Sent | N-15 | |
| Windshield Intermittent Wiper Switch Signal Is Not Sent | N-15 | |
| Windshield Low Speed Wiper Switch Signal Is Not Sent | N-15 | |
| Windshield High Speed Wiper Switch Signal Is Not Sent | N-15 | |
| Windshield Wiper Intermittent Intervals Adjusting Knob Signal Is Not Sent | N-16 | |
| Windshield Washer Switch Signal Is Not Sent | N-15 | |
| Transmitter | ||
| LOCK Switch Signal Is Not Sent to ETACS-ECU | N-17 | |
| UNLOCK Switch Signal Is Not Sent To ETACS-ECU | N-17 | |
| PANIC Switch Signal Is Not Sent To ETACS-ECU | N-17 | |