First MOT today for me today on my 2006 XK 150 Convertible.
I have had the car about 6 months . As I arrived and parked in front of the bay and looked down to see the words regarding pedestrian system , great. I turned the car off and after a quick chat with the tester over to him. He started the car and no warnings, the car now stays running for the next 40 mins whilst he does the test, no warnings on the dash.
Car on ramps, a shaker, brake tests, emission tests etc, no warnings.
Back car out of bay and hands over back to me , quick chat about emissions, apparently very very low and an advisory on rear bottom arms. Car is a pass.
I get back in car , start up and ABS and TCS comes up !
What a close call.



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Well done, mine's on Monday. Wish me luck

 

Sounds as if she needs a new battery,

Richard

 

The battery voltage is fine . The wheel sensors get confused on the brake test as it turns one axle at a time, whilst the other is stationary, hence the wheel sensors send confusing messages to the old ECU. It cleared within a mile . The other warning I have seen before once and cleared quickly, both times whilst slowly moving up to a wall and stopping. Again not the battery they need only 9.6v to operate , similar to many of the electrical circuits on the car .
If it happens again I will plug it in and take a look.

 

That's interesting. I've taken dozens of cars to various MOT stations with single axle brake testers over the last 20 years, with many of these being cars from the last 10 or 15 years including our 2006 XK, and have never seen the system registering an ABS or traction control fault as a result.

Richard

 

Hmmm...

 

Hi Cliffords,

I'm very curious about your source of the 9.6v specification. On most modern Jaguars, if the battery voltage sags below about 10.5 volts while cranking, the ECM will not trigger the ignition to start. And many solenoids in the vehicle (fuel injectors, purge valve, active exhaust solenoid, etc.) and other pulse-width-modulated components (fuel pump, radiator fan, etc.) may operate slowly on 9.6 volts, but they will not operate as quickly or reliably as they should (if they operate at all).

Cheers,

Don

 

#2, in the procedure attached.
We all know the number 1 cause for a fault detected in the can bus for tpms and epb.


cheers

 

Great news, she passed with no advisories