Self-Diagnosis Function (Mode 1)
- One second after you go into self-diagnosis function mode 1, the function starts to indicate the diagnosis trouble code (DTC), and repeats the DTC every three seconds.
- From mode 1, disconnect the SCS service connector for five to ten seconds, then reconnect the SCS service connector, and the function goes from mode 1 to mode 2.
NOTE: If no DTCs are indicated, but you know the system is abnormal, check these items:
- If the light does not come on and the buzzer does not beep, check the continuity between the BLK wire of the multiplex control inspection connector and body ground.
- If either the light or the beep indicates the DTC(s), check the continuity between the PNK/BLK wire of the multiplex control inspection connector and multiplex control units (driver's and passenger's).
Diagnostic Trouble Code (DTC) Table
NOTE: The numbers in the table show the troubleshooting sequence.
Communication Line Test
1. Continuity Test
Check for continuity according to the table.
- If there is continuity, go to step 2.
- If there is no continuity, check for an open in the wire.
2. Voltage Test
A. Turn the ignition switch ON (II).
B. Check for voltage between communication line and ground:
- If the voltage is too high:
A. Check for short to another wire.
B. Check for poor contact at the connector on the receiver side unit
C. Faulty circuit in the receiver side unit.
- If the voltage is too low:
A. Check for short to ground or to another wire.
B. Check for poor contact at the connector on the transmit side unit.
C. Faulty circuit in the transmitter side unit.
* If any control units appears to be faulty, select one control unit, substitute a known-good control unit, then recheck. If the system works properly, the original control unit is faulty; replace it. If there is still a malfunction, a substitute the known-good control unit for another control unit, then recheck. If the system works properly, that control unit is faulty; replace it.
Wake-up Function Test
Description:
- When the ignition switch is turned ON (II), all of the multiplex control units wake up at the same time. In this case, the wake up lines and communication lines are not involved in the wake up function.
- When a switch related to the multiplex control unit (door) is operated:
First, the door multiplex control unit wakes up, then the control unit starts to communicate to the driver's control unit. By this communication, the driver's control unit wakes up. The driver's control unit wakes the passenger's control unit up by the wake up line, and all the control units start to function.
- When a switch related to the multiplex control unit (driver's or passenger's) is operated:
The control unit related to the operated switch wakes up, then the control unit wakes up the other unit. (In this case, the door control unit does not wake up.)
Related Switch (Input):
The switches and input signals that can wake up the multiplex control unit are shown:
Related Switch (Input) Table:
Confirming the Function
1. Shifting to the sleep mode:
1. Turn the ignition switch OFF.
2. Cancel the key-off operation timer in power window system by opening and closing one of the front doors.
3. Make sure that the trunk is closed, and exterior lights are off.
4. If you do not operate the switches related to the multiplex control units more than one minute after meeting the above conditions, the system function shifts to the sleep mode.
(All of the switches must be turned OFF except door lock knob switches, ignition key switch, audio switch, and hood switch.)
2. Confirming the sleep mode:
1. Check for voltage between the wake up line (PNK/BLU wire between driver's and passenger's control unit). There should be no voltage with the sleep mode OFF.
There should be battery voltage with the sleep mode ON.
2. Check for voltage between each communication line and body ground while shifting to the sleep mode. There should be no voltage.
3. Check the parasitic draw at the battery while shifting to the sleep mode. The ampere should change from 100 mA to less than 100 mA.
3. Confirming the wake up mode:
After confirming the sleep mode, turn the related switch ON, and wake up each control unit. If all of the operations works properly, the wake up mode is OK.
(If any of the control units are faulty and cannot wake up, several parts of the system will not work at the same time.)
Faulty Wake-Up Line Symptoms
Open in the line:
Most of the systems do not operate because one of the control units cannot wake up the other control units. But the control unit that is not awake can wake up by operating a switch related to the control unit.
All of the control units wake up by turning the ignition switch ON (II).
Short in the line:
- If the line is shorted to body ground:
- The control units (driver's and passenger's) cannot wake up except with the ignition switch ON and the wake up signal from the door unit.
- The control unit (driver's) can wake up by a switch operation related to the control unit (door), but the control unit (passenger's) cannot wake up by a switch operation.
- All of the control units wake up by turning the ignition switch ON (II).
- If the line is shorted to a battery voltage (+) line:
- Most of the systems do not operate because one of the control units cannot wake up the other control units.
- Possible a blown fuse or a faulty transistor in the control unit.
- The control unit can wake up by a related switch operation, but the other control units cannot wake up.
- The control unit (driver's) can wake up by a switch operation related to the control unit (door), but the control unit (passenger's) cannot wake up by a switch operation.
- All of the control units wake up by turning the ignition switch ON (II).
Check the Wake-Up Function
Check the wake-up lines:
Check for continuity of each line. There should be continuity.
- If there is no continuity, the line is open.
- If there is continuity, go to next step.
Check for voltage between each control units with the wake-up lines connected. There should be no voltage in the wake-up mode, and there should be battery voltage in the sleep mode.
If the voltages are not specified, disconnect the wake-up line connector of one control unit, and recheck. Then connect it, and disconnect the wake up line connector of another control unit, and recheck.
- If the voltage are not specified on both sides of the line, the wake-up line is shorted to another wire or body ground.
- If the voltages are not specified on one side of the line, inspect the connector and socket terminals to be sure they are all making good contact. If the terminals are OK, the possible cause is a disconnected wake-up line in the control unit.