Maintenance: Service and Repair

Fig. 1 Stop Fuse Location:

The check engine lamp will be illuminated when the ignition switch is in the On position, when engine is not operating. When engine is started, the Check Engine lamp should go off. If lamp remains on, the Electronic Control Unit (ECU) has stored a code, or detected an abnormality in the system. After diagnosis and repair, place ignition switch in Off position, then clear codes stored in the ECU memory by removing the STOP (15A) fuse for at least 10 seconds on all except all 1990-92 Tercel models. On 1990-92 Tercel, remove the EFI (15A) fuse for at least 10 seconds. The colder the ambient temperature, the longer the fuse should be left out. The fuse is in the relay panel, located on the lefthand side of the kick panel, Fig. 1. Another method to erase stored codes is to disconnect the battery negative cable. This method will also erase any other stored memories, such as the clock and radio.