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.
2004 Chevrolet Epica LSFACTORY OEM SERVICE PROCEDURE
Transmitter Synchronization: Notes
IMPORTANT:
Synchronization may be necessary under the following conditions
- If the immobilizer programming procedure has been performed.
- If the transmitter is activated more than 255 times while the transmitter is out of range of the intelligent switching unit's antenna
- Synchronization may be necessary due to the security method used by the remove keyless entry system. The transmitter does not send the same signal twice to the intelligent switching unit (ISU).
- The ISU will not respond to a signal that has been sent previously. This prevents anyone from recording and playing back the signal from the transmitter.
- The battery in the transmitter was replaced.
- The battery in the vehicle has been in a low or no charge condition for an extreme period of time.
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.