Fault with my brothers Fiesta ST

saitrix · 19 Apr 2011 at 20:14

Hi,

My brothers just got home saying some lights on his dash has come on and his speedo wasn't working. He has got the ABS light (flashing), engine warning light and transmission/engine systems warning light. So got it into test mode to get the DTC codes for it. They are C121, E197, E200, E510 and C100. Which when looking up I have found it seems to ring true with vehicle speed sensor and/or wheel speed sensor. Though from what I found on forums no one ever had all 5 of these codes come up for it.

Now I wouldn't think the vehicle speed sensor (on the gearbox) would be used at all to operate the ABS so I don't understand why it would kick out the ABS faults. So then it made me think whether it was the wheel speed sensor but that isn't used for the speedo at all. Finally did think whether it could be a loose connection but I don't really know where I'd even start looking.

Anyone have any ideas?

Biohazard · 19 Apr 2011 at 20:44

Wheel speed sensor is for the ABS

Lashout_UK · 19 Apr 2011 at 20:45

It'll most likely be throwing the ABS light because it's seeing a difference between the wheel speed sensor and the vehicle speed sensor - so the ABS can't work out what's going on and is just defaulting to a fault mode for safety reasons

saitrix · 19 Apr 2011 at 21:05

Lashout_UK said:
It'll most likely be throwing the ABS light because it's seeing a difference between the wheel speed sensor and the vehicle speed sensor - so the ABS can't work out what's going on and is just defaulting to a fault mode for safety reasons

Hmm good point there. Tomorrow I will find the sensor, see if the connection isn't loose at all first. If not it seems it is £40 so not bad price really.

Biohazard, Yes it is, but the speed sensor on the gearbox isn't.