Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2007 Suzuki SX4 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Differential DTCS
DIFFERENTIAL DIAGNOSTIC TROUBLE CODE (DTC) LIST
| DTC | Detecting item | Detecting condition (DTC will set when detecting) |
|---|---|---|
| C1240 | 4WD control module power supply circuit malfunction | Battery voltage is lower than lower limit voltage for 4WD control module diagnosis. |
| C1243 | Internal circuit malfunction of 4WD control module | Internal power supply malfunction of 4WD control module |
| C1250 | Coupling air temperature sensor open | Sensor output voltage too high |
| C1251 | Coupling air temperature sensor short | Sensor output voltage too low |
| C1252 | Coupling assembly open | 2WD/4WD switch is changed of 4WD lock position, and then vehicle is not changed for more than 5 seconds. |
| C1253 | Coupling assembly short | 2WD/4WD switch is changed of 4WD lock position, and then vehicle is not changed for more than 5 seconds. |
| C1254 | 2WD/4WD switch malfunction | Different switch combination from specification is detected more than 5 seconds. |
| U0073 | Control module communication bus off | Transmitting and receiving error of 4WD control module for specified time continuously |
| U0100 | Lost communication with ECM | Receiving error of 4WD control module from ECM for specified time continuously |
| U0121 | Lost communication with ABS / ESP® control module | Receiving error of 4WD control module from ABS / ESP® control module for specified time continuously |
| U0155 | Lost communication with instrument panel cluster control module | Receiving error of 4WD control module from combination meter for specified time continuously |
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.