2002 Honda Civic Power Loss with Diagnostic Code P1298 - ELD Module Failure and O2 Sensor Fix
The 2002 Honda Civic may experience sudden power loss accompanied by diagnostic trouble code P1298. While accessory fuses in both the engine compartment and under-dash fuse box appear intact, this issue is often linked to the Electronic Load Device (ELD) module. The ELD, integrated into the under-dash fuse box, functions similarly to an electronic throttle position sensor (TPS), monitoring current flow to allow the Engine Control Module (ECM) to manage the charging system. According to Honda Technical Service Bulletin #05-006, the ELD is now sold separately from its original fuse box assembly. To diagnose the ELD: 1. Confirm that the Black (BLK) wire is grounded; 2. Verify the Green/Yellow (GRN/YEL) wire has battery voltage; 3. Ensure the Green/Red (GRN/RED) wire shows 4.5 to 5 volts reference when unplugged. With the ELD connector connected and the engine running, as accessories are turned on, the GRN/RED voltage should drop from approximately 3 volts under no load to 1.5 volts during high load. If this voltage does not change, the ELD is likely faulty and must be replaced. Additionally, some users have reported that replacing the primary oxygen (O2) sensor resolves power loss symptoms in certain cases. However, this solution may vary by vehicle configuration. For accurate troubleshooting, it's essential to identify which specific circuit is affected. Referencing wiring diagrams can help determine the correct fuse number associated with each accessory circuit.
Yes, some accessories are powered through the in-dash fuse box, while others originate from the engine compartment fuse box. The ELD module is located within the under-dash unit and plays a key role in charging system regulation.