4200 speedo not working

[jluis]

Is this similar on a 3200?
I've just changed rear shoes and after a brief run on the axle stands now have no speedo, a CEL, ABS light on and No ASR on
It's too bright in the cabin with all the warning lights!

Maybe you nicked a wheel speed sensor?
Still won't explain the CEL.

 

[jluis]

Well, you already replaced the CAN bridge and both the speedo and SATNAV are separate units.
I think the only thing left that can be causing you the issue is the CAN bus from the bridge unit to the speedo/SATNAV.
Unfortunately a CAN bus is a shared medium and your problem can be caused by bad wiring or a peripheral on the CAN bus shorting the bus or corrupting it.

If you have an electric diagram to see where the bus runs trough, start disconnecting peripherals one at a time and see if the problem goes away.
You might also want to check the cable that goes into the CAN bridge with a multimeter to see if it's shorted or not.

Jaguars had a problem in the infotaiment BUS that if one element connected to the BUS is failed or removed the entire system stops working.

 

[Contigo]

Check Engine light comes up when you disturb the Speed sensor. Clear it down in unidiag or with OBD scan tool and it will go off. Mine was lot when I did the rear brake discs.

 

[Gp79]

Check this link, it will help with diagnostics on the abs.

It is for a BMW, but Maserati 4200 / GS share the same bosch unit, it helped me when I had a wheel sensor fail.

http://www.bimmerfest.com/forums/showpost.php?p=4205801

 

[RSM Masser]

Happy to report the No/Asr and ABS light where a very simple fix.
Simply replace wheels - drive up road, brake, return home - lights off!

Apparently engaging drive with the rear wheels in the air causes the computer to throw a wobbly, 2 wheels turning, 2 not. driving up the road computer breathes sigh of relief - situation normal.

 

[Contigo]

Happy to report the No/Asr and ABS light where a very simple fix.
Simply replace wheels - drive up road, brake, return home - lights off!

Apparently engaging drive with the rear wheels in the air causes the computer to throw a wobbly, 2 wheels turning, 2 not. driving up the road computer breathes sigh of relief - situation normal.

Yep simple fix. Same with mine as I said.

 

[Steve4200]

Will look at Canbus Wiring ,

The strange thing is that this fault does NOT bring up the ABS fault light !
Just NO ASR , NO SPEEDO and NO TRIP DATA
Vehicle speed is showing if engine ECU interrogated , Bridge Can and Speedo Dial is ok.

 

[gilbey]

Steve4200,

Did you ever get to the bottom of this fault, as I seem to be having a similar problem with my 4200. Any help appreciated.

 

[Steve4200]

Steve4200,

Did you ever get to the bottom of this fault, as I seem to be having a similar problem with my 4200. Any help appreciated.

Yes, It turned out to be the incorrect ABS ECU being fitted by previous owner/s.
This ABS ECU worked for ABS function but as it’s firmware was not for Maserati 4200 the speed data could not be read by the bridge CAN module and in turn no speed pulses sent to the speedometer, no trip data or ASR function.

SPEEDOMETER :-
Wheel Speed Sensors to ABS ECU which sends speed data via C- CANBUS to BRIDGE CAN ECU which sends speed pulses to Speedometer.

TRIP COMPUTER :-
Wheel Speed Sensors to ABS ECU which sends speed data via C-CANBUS to BRIDGE CAN ECU which sends trip data via B-CANBUS to NIT Trip Computer.

ASR FUNCTION :-
ASR button to BRIDGE CAN ECU which sends ASR command to ABS ECU via C-CANBUS.

ABS ECU sends ASR status data via C-CANBUS to BRIDGE CAN ECU which illuminates the ASR button Led and ASR Dash indication.


Regards