p0134
Easy Fix
Honda · Sedans
O2 Sensor Circuit No Activity Detected Bank 1 Sensor 1
Quick Answer
Error code P0134 on your Honda Sedans means: O2 Sensor Circuit No Activity Detected Bank 1 Sensor 1. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
  1. Faulty upstream oxygen sensor (Bank 1, Sensor 1)
  2. Damaged or corroded O2 sensor wiring or connector
  3. Exhaust leak before the upstream O2 sensor
  4. Blown O2 sensor heater circuit fuse
  5. ECM/PCM issue preventing proper O2 sensor bias voltage
How to Fix It
1
Check the O2 sensor fuse in the under-hood fuse box; replace if blown
2
Inspect the upstream O2 sensor connector and wiring for damage, corrosion, or rodent chews
3
Monitor the Bank 1 Sensor 1 voltage with a scan tool at idle; it should oscillate between 0.1V and 0.9V
4
Check for exhaust leaks at the exhaust manifold and header connections
5
Replace the upstream oxygen sensor if the signal is flat or not switching
Pro Tip
This is a common issue that most users can resolve without specialized tools. Try the first step before moving on to more complex solutions.
Parts You May Need
Upstream oxygen sensor (Bank 1, Sensor 1)
O2 sensor wiring harness
Exhaust manifold gasket
O2 sensor fuse
Related Error Codes
Video Guides
Loading video guides…
Search more on YouTube →