OK, so I drive down to get my new outer rear CV joint this morning.
All is well with the cargot a hair over 26MPG for drive down.
I drive out of the dealership and get back on the highway and
look down and speedometer says I am only doing like 30 MPH????
Should be reading like 65MPH. I pull over, shutdown, restart.
No good, same thing, speedo not reading right. I had my scan tool
still in the car so I pulled over again and hooked it up and ran it in
"monitor" mode to see if te MPH was registering via the OBD port.
Nada! MPH stayed a 0 while driving. The engine RPM reading from
the scan tool was fine, was the same as the dash Tach.

Where does the Speedo get it's signal from? Is there a Vehicle Speed
Sensor? No code is being set for this. I rescanned and just got
P1111, and the C1175 I went to get the new outer CV joint for.
(P1111 just means all "readyness" tests complete)

So new I have a dash lit up like a Holiday tree due to the ABS fault
and a speedo that only "half works"!!! AHHHHHH!

Any ideas????

Thanks!

 

The vehicle has 4 wheel speed sensors so the ECU knows how fast each wheel is going.
The 2 rear wheel outer CV joints each have aring which is where thespeedinfo is taken from.
Fault with the new part maybe due to still getting the C1175 code with the new outer CV joint?

 

The new outer CV joint is not in yet. I just drove down to pick up the
new one this morning. When I drove away the speedo was not working
right. BTW I found the left rear speed ring detached so it is not even
on the CV joint anymore.

I've had the C1175 for a week now and the Speedo just started
acting up today. Was wondering if there is a "main" Vechicle
Speed Sensor. I was under the impression the sensors at the
wheels were only for the ABS module???

 

Bo Knows!

Thanks for the info! I asked the Jag Tech @ the
dealership what size the CV Joint hub nut is.
He told me 32mm. I knew I did not have one so
I picked one up on the way home. I pulled the tire
off yesterday to make sure it was 32mm and it is.
I looked in back of the caliper and low and behold
there was the sensor ring hanging on the CV boot!
It was snapped in one place. I was able to "unclip"
it from the axle. I would imagine that the ring was
somewhat in place and sending a partial speed signal
to the ECM. Driving at sustained highway speeds yesterday
must have sent the ring flying off and causing the Speedo
malfuntion??? Sounds like a good guess anyway!

I can't get to replacing the joint until next Wed. Have to
work this weekend through Tues. I am hoping to snap
step by step pics of this procedure and maybe write it up
for the FAQ. BTW the Jag Tech atthe dealershipsaid it takes
him about 2 hours.

Agian, like to thank all for the help on this!

 

You mean like the one already in there
https://www.jaguarforums.com/m_17160/tm.htm

PS When mine came off it didnt affect the speedo reading.

 

Just to close out this tread too, replacing my rear
outer CV joint fixed the speedo issue along with
the ABS and DSC faults.

I noticed that the speedo was reading about half!
I think my odometer was only ringing up half my
milage too! All fixed now!

Thank you Bo for noting you had the same issue
when your speed ring went.