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Matt, Engineer
Category: Jaguar
Satisfied Customers: 21615
Experience:  Mechanical Engineer with 20 years experience in the auto industry, 8 yrs in formula 1 engine testing
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My jag needs to be smog tested. A few days ago, the O2

Customer Question

my jag needs to be smog tested. A few days ago, the O2 sensor was replaced. Now, the O2S and CAT monitors will not reset.
JA: Have you located all of the vehicle's oxygen sensors? Are the wires leading to and from each intact and in good shape?
Customer: they were all replaced. 700 dollars.
JA: What is the model/year of your Jaguar?
Customer: it is a van den plan.1999
JA: Are you fixing your vehicle yourself? What have you tried so far?
Customer: i did not know there was a problem until i took it in to be smog tested. then i found out that the repair of the O2 sensor caused the OBD to essentially reset. all monitors have reset except the CAT and the O2.
JA: Anything else you want the mechanic to know before I connect you?
Customer: no
Submitted: 2 months ago.
Category: Jaguar
Expert:  Matt replied 2 months ago.


this sounds like the car is awaiting the drive cycle / test cycle to be completed

Jag's of this era need a specific sequence of engine and load to be completed to enable the O2 functionality

try these drive cycles:

Evaporative Emissions Control System
Fuel tank level between 15% - 85% full; after start-up, run engine (idle) for at least 7 minutes. With engine at normal operating temperature, drive vehicle 39 - 50 mph – (62 - 80 km/h) for at least 6 minutes.

Catalytic Converter Efficiency
Ambient (IATS) temperature > 20 °C (68 °F); engine at normal operating temperature; normal, varied driving for 3 minutes; then, constant steady throttle 50 – 60 mph (80 – 95 km/h), 1500 – 2300 > 15 seconds; then, constant steady throttle 30 – 38 mph (50 – 60 km/h), 1100 – 1900 rpm > 15 seconds

O2 sensors
Ambient temperature < 70 °C (158 °F); engine at normal operating temperature drive at steady speed > 13 mph (20 km/h) > 1 minute 10 seconds