• The gear in the top of the box rotates.
• Sensor has power.
• Spun the sensor with my fingers, nothing happens.
• Replaced the speedo sensor.
• Doesn't seem to be continuity from the signal wire (at the sensor end) to the signal wire (at pin 17 of MCU). So...
• Ran my own wires (signal and ground) straight from the sensor to pins 15 and 17 on the MCU by the fuse box (as per wiring diagram).
• Used a diag tool to test the clocks, speedo needle moves fine in test mode.

MattHubbert77 said:

Hi all. I have a 04 Punto (3 door). The speedo hasn't worked since I've had it, and looking at the MOT certificates it hasn't worked for 3 years.
I'm looking for someone with considerable experience with these things, because I've tried almost everything to repair it, all to no avail.
For clarity, I have the non-abs model, and it gets its speed from a sensor in the top of the gearbox. A signal and ground wire goes from the sensor to the MCU (box behind the fuse box near steering wheel).

Here's what I know / I've tried so far -

• The gear in the top of the box rotates.
• Sensor has power.
• Spun the sensor with my fingers, nothing happens.
• Replaced the speedo sensor.
• Doesn't seem to be continuity from the signal wire (at the sensor end) to the signal wire (at pin 17 of MCU). So...
• Ran my own wires (signal and ground) straight from the sensor to pins 15 and 17 on the MCU by the fuse box (as per wiring diagram).
• Used a diag tool to test the clocks, speedo needle moves fine in test mode.

The last option I see is replacing the MCU, perhaps its fried? But I'd need to replace the ECU and all the keys - not really interested.

Anybody got any more options for me?

As a side note, the diagnostic module also gives the following warnings -
"C1012 Vehicle Speed (From CAN)"
"C1006 Steering columns motor torque position sensors"

Is the latter an easy fix? Assisted steering seemed to half in power when this error came up (Red steering wheel light in dashboard, too).

Cheers guys.

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