General Precautions
- Always use a 12 volt battery as power source.
- Do not attempt to disconnect battery cables while engine is running.
- Do not disassemble ECUs.
- If the battery is disconnected, the following emission-related diagnostic information will be lost within 3 minutes.
- Diagnostic trouble codes
- Freeze frame data
- When connecting the hybrid vehicle control ECU harness connector, fasten it securely with a lever as far as it will go as shown in the figure.
- When connecting or disconnecting pin connectors into or from the hybrid vehicle control ECU, take care not to damage pin terminals (bend or break).
Make sure that there are not any bends or breaks on the hybrid vehicle control ECU pin terminal, when connecting pin connectors.
- Securely connect the hybrid vehicle control ECU harness connectors.
A poor connection can cause an extremely high (surge) voltage to develop in coil and condenser, thus resulting in damage to ICs.
- Keep hybrid vehicle control system harness at least 10 cm (4 in) away from adjacent harness, to prevent hybrid vehicle control system malfunctions due to receiving external noise, degraded operation of ICs, etc.
- Keep hybrid vehicle control system parts and harness dry.
- When measuring ECU signals with a circuit tester, never allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and damage the ECU power transistor.
- When installing C.B. ham radio or a mobile phone, be sure to observe the following as it may adversely affect electronic control systems depending on installation location.
- Keep the antenna as far as possible from the electronic control units.
- Keep the antenna feeder line more than 20 cm (8 in) away from the harness of electronic controls.
Do not let them run parallel for a long distance.
- Adjust the antenna and feeder line so that the standing-wave radio can be kept smaller.
- Be sure to ground the radio to vehicle body.