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Land Rover Repair/o2 heate sensor not cycling


hello john:
I have a 1996 range rover 4.0 se and I need o have I smog but some how the computer cycle wont complete the o2 heater sensor and the evap. wont cycle had the sensors check they're getting power and he sensors had been replaced but they wont cycle it keeps saying that the o2 sensor heater incomplete cycle the evap. is not a problem because the sate allow it o be incomplete to pass the smog here in California.......

I have ** TWO ** other issues going with my P38 I have the *SRS* light on but never has been hit it just turned on after a heavy rain and at random I get a message hat my brake fluid is low how ever I just had the brakes flushed and the level is to the level it requires could this two issues cause the computer not o complete the drive cycle is there some thing else that I nee to do to make the computer complete the drive cycle

the reason I ask if this two issues affect he completion of the cycle is because my friend had a Mercedes brake switch not working and it would interrupt the completion of the drive cycle
thanks for taking the time to help.....

The only way to answer your question will be to connect a diagnostic computer and look at the live data from all the sensors as the engine warms up.  You should be able to see something out of range or non responsive, to account for the failure to go into closed loop.  There is no single answer for the problem; it could be anything

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John Elder Robison


I own J E Robison Service in Springfield, MA. We are Bosch Car Service for Land Rover, BMW, Mercedes, and other European lines. I can answer most questions about Land Rover service or repair. I'm known as a car enthusiast, machine aficianado, photographer, writer, and speaker. I've been around Land Rovers and British cars most of my life. Visit me at my car business, or my author website, Check out my autism and writing blog at or my photos on John Elder Robison


I have been a Land Rover service manager since Land Rover returned to North America in 1987. My company is a four-star Bosch Car Service facility, known nationwide for Land Rover service, overhaul, customization, and restoration. In addition to Land Rover our company services BMW, Jaguar, Mercedes-Benz, Rolls_Royce, and Bentley motorcars. We have factory-plus-level service capability for all makes. Visit my company online at > service > land rover Also visit my blog at


In the Land Rover world, my writing can be found in various print magazines and online at robisonservice.blogspot,com. In the wider publishing world, my work is published by 20 publishers in over 50 countries. Mt books Look Me in the Eye, Be Different and Raising Cubby have made US and international bestseller lists.

I am ASE certified, Bosch Trained, and trained by Omnitec/T4 and Autologic on their Land Rover test systems.

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