Author Topic: Fault Codes : 1 - : 304 : Oxygen (Lambda) Sensor Circuit Malfunction, No signal  (Read 7200 times)

MikePDX

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I have an '03 F650GS (single spark) and I'm getting the fault code "Fault Codes : 1
- :
304 : Oxygen (Lambda) Sensor Circuit Malfunction, No signal or signal intermittent
Currently present : NO
Occurrence count : 7"

No operating issues but I want to head off any potential problems. Replace lambda sensor, clean it, ignore? 

WayneC

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I would check the usual suspects in harness chafing particularly around the rear shock adjuster mount then look at the wiring back to the sensor before I replaced anything, a continual fault code on the 02 sensor would suggest either poor connection or faulty sensor

TAJL

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Have you taken a look at the O2 graph function to see if there is a lambda signal or a flat line as your fault code would suggest?

MikePDX

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Thanks for the responses. I haven't had a chance to get back into the garage and try what's been suggested. I've got to go fishing today and have a ride tomorrow.  I'll have a look in the next day or so and post my findings.