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Problem Symptoms Table

DTC INDEX

DTC Description
DTC C1713/13, C1714/14  RIGHT REAR HEIGHT CONTROL SENSOR CIRCUIT, LEFT REAR HEIGHT CONTROL SENSOR CIRCUIT
DTC C1715/15, C1716/16, C1717/17, C1791/91, C1792/92, C1793/93  RIGHT FRONT ACCELERATION SENSOR CIRCUIT, LEFT FRONT ACCELERATION SENSOR CIRCUIT, REAR ACCELERATION SENSOR CIRCUIT, RIGHT FRONT ACCELERATION SENSOR CIRCUIT, LEFT FRONT ACCELERATION SENSOR CIRCUIT, REAR ACCELERATION SENSOR CIRCUIT
DTC C1725/25, C1726/26, C1727/27, C1728/28  RIGHT FRONT ABSORBER CONTROL ACTUATOR CIRCUIT, LEFT FRONT ABSORBER CONTROL ACTUATOR CIRCUIT, RIGHT REAR ABSORBER CONTROL ACTUATOR CIRCUIT, LEFT REAR ABSORBER CONTROL ACTUATOR CIRCUIT
DTC C1733/33, C1734/34, C1735/35, C1744/44  GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT
DTC C1741/41  AIR SUS RELAY CIRCUIT
DTC C1742/42  HEIGHT CONTROL COMPRESSOR CIRCUIT
DTC C1751/51  CONTINUOUS ELECTRIC CURRENT TO HEIGHT CONTROL COMPRESSOR
DTC C1761/61  ECU MALFUNCTION
DTC C1774/74  POWER SOURCE CIRCUIT
DTC C1776/76, C1794/94, C1795/95  SPEED SENSOR CIRCUIT, RIGHT FRONT SPEED SENSOR CIRCUIT, LEFT FRONT SPEED SENSOR CIRCUIT
DTC C1777/77  STEERING ANGLE SENSOR CIRCUIT
DTC C1779/79, C1797/97  CRANKSHAFT POSITION SENSOR CIRCUIT, CRANKSHAFT POSITION SENSOR CIRCUIT
DTC C1782/82  STOP LIGHT SWITCH CIRCUIT
DTC C1783/83  DOOR COURTESY SWITCH CIRCUIT
DTC C1786/86  HEIGHT CONTROL SWITCH CIRCUIT
DTC C1787/87  ABSORBER CONTROL SWITCH CIRCUIT
DTC C1788/88  HEIGHT CONTROL OFF SWITCH CIRCUIT

If a normal code is displayed during the DTC check but the problem still occurs, check the circuits for each problem symptom in the order given in the table below and proceed to the relevant troubleshooting page.

HINT:

Inspect each malfunction circuit in numerical order for the corresponding symptom.

If the malfunction still exist even after checking and confirming that all the circuit are normal, replace the suspension control ECU.

PROBLEM SYMPTOMS

Symptom Suspect Area Action
Vehicle height control function does not operate
  1. Freezing of the air tube
  2. Power source circuit
  3. Crankshaft position sensor circuit
  4. Height control OFF switch circuit
  5. Height control switch circuit
  6. Height control sensor circuit
  7. Height control solenoid valve circuit
  8. Gate solenoid valve circuit
  9. Exhaust solenoid valve circuit
  10. AIR SUS relay circuit
  11. Height control compressor circuit
  12. Suspension control ECU
  1. -
  2. DTC C1776/76, C1794/94, C1795/95: SPEED SENSOR CIRCUIT, RIGHT FRONT SPEED SENSOR CIRCUIT, LEFT FRONT SPEED SENSOR CIRCUIT 
  3. DTC C1779/79, C1797/97: CRANKSHAFT POSITION SENSOR CIRCUIT, CRANKSHAFT POSITION SENSOR CIRCUIT 
  4. DTC C1788/88: HEIGHT CONTROL OFF SWITCH CIRCUIT 
  5. DTC C1786/86: HEIGHT CONTROL SWITCH CIRCUIT 
  6. DTC C1713/13, C1714/14: RIGHT REAR HEIGHT CONTROL SENSOR CIRCUIT, LEFT REAR HEIGHT CONTROL SENSOR CIRCUIT 
  7. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  8. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  9. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  10. DTC C1741/41: AIR SUS RELAY CIRCUIT 
  11. DTC C1742/42: HEIGHT CONTROL COMPRESSOR CIRCUIT 
  12. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Illuminated up position of height control indicator lamp does not change by the height control switch operation
  1. Power source circuit
  2. Crankshaft position sensor circuit
  3. Height control OFF switch circuit
  4. Height control switch circuit
  5. Height control sensor circuit
  6. Height control solenoid valve circuit
  7. Gate solenoid valve circuit
  8. Exhaust solenoid valve circuit
  9. AIR SUS relay circuit
  10. Height control compressor circuit
  11. Speed sensor circuit
  12. Suspension control ECU
  1. DTC C1776/76, C1794/94, C1795/95: SPEED SENSOR CIRCUIT, RIGHT FRONT SPEED SENSOR CIRCUIT, LEFT FRONT SPEED SENSOR CIRCUIT 
  2. DTC C1779/79, C1797/97: CRANKSHAFT POSITION SENSOR CIRCUIT, CRANKSHAFT POSITION SENSOR CIRCUIT 
  3. DTC C1788/88: HEIGHT CONTROL OFF SWITCH CIRCUIT 
  4. DTC C1786/86: HEIGHT CONTROL SWITCH CIRCUIT 
  5. DTC C1713/13, C1714/14: RIGHT REAR HEIGHT CONTROL SENSOR CIRCUIT, LEFT REAR HEIGHT CONTROL SENSOR CIRCUIT 
  6. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  7. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  8. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  9. DTC C1741/41: AIR SUS RELAY CIRCUIT 
  10. DTC C1742/42: HEIGHT CONTROL COMPRESSOR CIRCUIT 
  11. DTC C1776/76, C1794/94, C1795/95: SPEED SENSOR CIRCUIT, RIGHT FRONT SPEED SENSOR CIRCUIT, LEFT FRONT SPEED SENSOR CIRCUIT 
  12. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Hunting of vehicle height occurs
  1. Air leakage (Height control cylinder assy rear)
  2. Height control sensor circuit
  3. Suspension control ECU
  1. ON-VEHICLE INSPECTION
  2. DTC C1713/13, C1714/14: RIGHT REAR HEIGHT CONTROL SENSOR CIRCUIT, LEFT REAR HEIGHT CONTROL SENSOR CIRCUIT 
  3. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Vehicle height control operates, but vehicle height is uneven
  1. Air leakage
  2. Clogging of the Air tube
  3. Height control sensor link sub-assy
  4. Height control sensor circuit
  5. Gate solenoid valve circuit
  6. Suspension control ECU
  1. ON-VEHICLE INSPECTION
  2. -
  3. ON-VEHICLE INSPECTION
  4. DTC C1713/13, C1714/14: RIGHT REAR HEIGHT CONTROL SENSOR CIRCUIT, LEFT REAR HEIGHT CONTROL SENSOR CIRCUIT 
  5. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  6. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Vehicle height control operates, but vehicle height is high or low: (Vehicle height in NORMAL mode differs from the standard value)
  1. Height control sensor link sub-assy
  2. Height control sensor circuit
  3. Suspension control ECU
  1. ON-VEHICLE INSPECTION
  2. DTC C1713/13, C1714/14: RIGHT REAR HEIGHT CONTROL SENSOR CIRCUIT, LEFT REAR HEIGHT CONTROL SENSOR CIRCUIT 
  3. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
When vehicle height control is adjusted, it stops at extremely high or extremely low position
  1. Height control sensor circuit
  2. Height control sensor link sub-assy
  3. Suspension control ECU
  1. DTC C1713/13, C1714/14: RIGHT REAR HEIGHT CONTROL SENSOR CIRCUIT, LEFT REAR HEIGHT CONTROL SENSOR CIRCUIT 
  2. ON-VEHICLE INSPECTION
  3. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Height control OFF indicator lamp condition is abnormal
  1. Power source circuit
  2. Height control OFF switch circuit
  3. Height control OFF indicator lamp circuit
  4. Suspension control ECU
  1. DTC C1774/74: POWER SOURCE CIRCUIT 
  2. DTC C1788/88: HEIGHT CONTROL OFF SWITCH CIRCUIT 
  3. HEIGHT CONTROL OFF INDICATOR LAMP CIRCUIT 
  4. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Height control indicator lamp condition is abnormal
  1. Power source circuit
  2. Height control indicator lamp circuit
  3. Suspension control ECU
  1. DTC C1774/74: POWER SOURCE CIRCUIT 
  2. HEIGHT CONTROL INDICATOR LAMP CIRCUIT 
  3. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
DTC check cannot be completed
  1. Power source circuit
  2. TC terminal circuit
  3. Height control OFF indicator lamp circuit
  4. Suspension control ECU
  1. DTC C1774/74: POWER SOURCE CIRCUIT 
  2. TC TERMINAL CIRCUIT 
  3. HEIGHT CONTROL OFF INDICATOR LAMP CIRCUIT 
  4. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Input signal check (Test mode) cannot be completed
  1. Power source circuit
  2. TS terminal circuit
  3. Suspension control ECU
  1. DTC C1774/74: POWER SOURCE CIRCUIT 
  2. TS TERMINAL CIRCUIT 
  3. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Vehicle height is extremely low when vehicle is parked Although, especially in a cold district, the vehicle height may become lower due to the air temperature drop in the height control cylinder assy, that is not abnormal.
  1. Air leakage
  2. Height control cylinder assy rear
  3. Height control sensor link sub-assy
  4. Height control solenoid valve circuit
  5. Exhaust valve circuit
  1. SUSPENSION CONTROL SYSTEM
  2. PNEUMATIC CYLINDER
  3. SUSPENSION CONTROL SYSTEM
  4. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  5. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
Compressor motor continues to operate Due to the air tube freezing, vehicle height may not rise all the time.
  1. Air leakage
  2. Air tube clogged
  3. Height control cylinder assy rear
  4. Height control sensor link sub-assy
  5. Height control solenoid valve circuit
  6. Exhaust valve circuit
  7. Tank solenoid valve circuit
  8. AIR SUS relay circuit
  9. Height control compressor circuit
  10. Suspension control ECU
  1. SUSPENSION CONTROL SYSTEM
  2. -
  3. PNEUMATIC CYLINDER
  4. SUSPENSION CONTROL SYSTEM
  5. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  6. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  7. DTC C1733/33, C1734/34, C1735/35, C1744/44: GATE SOLENOID VALVE CIRCUIT, LEVELING SOLENOID VALVE CIRCUIT, EXHAUST SOLENOID VALVE CIRCUIT, TANK SOLENOID VALVE CIRCUIT 
  8. DTC C1741/41: AIR SUS RELAY CIRCUIT 
  9. DTC C1742/42: HEIGHT CONTROL COMPRESSOR CIRCUIT 
  10. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
Damping force control does not operate at all
  1. Absorber control actuator circuit
  2. TS terminal circuit
  3. Shock absorber
  4. Suspension control ECU
  1. DTC C1725/25, C1726/26, C1727/27, C1728/28: RIGHT FRONT ABSORBER CONTROL ACTUATOR CIRCUIT, LEFT FRONT ABSORBER CONTROL ACTUATOR CIRCUIT, RIGHT REAR ABSORBER CONTROL ACTUATOR CIRCUIT, LEFT REAR ABSORBER CONTROL ACTUATOR CIRCUIT 
  2. TS TERMINAL CIRCUIT 
  3. FRONT SHOCK ABSORBER WITH COIL SPRING ;SHOCK ABSORBER
  4. ELECTRONIC CIRCUIT INSPECTION PROCEDURE
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