What was the original problem again?

The Teves Mk 2 on the Sierra has no Keep Alive Memory, so it doesn't remember a thing when it's turned on the next time. As a result, it stores no fault codes - all faults that are indicated are 'live', not old.

Have you done the measurements at the ABS ECU's multiplug? If not, do that - it's all very well a sensor 'checking out', but if the ECU can't see it because of a wiring fault, it might as well not be there.

• Wheel sensors should be anywhere between 800 and 1400 ohms.
• The outlet solenoids in the valve block should register between 2 and 5 ohms.
• The inlet solenoids in the valve block should register between 3 and 7 ohms.
• The mail valve should be between 2 and 5 ohms.

• The fluid level switch (two pin plug on top of the fluid reservoir) can be measured across pins 9 and 10 of the ECU multiplug - this should be a closed circuit when the fluid level is at max, and open when it's higher or lower. If this switch is open, the ABS will be disabled. This was the problem with mine.
• The wheel sensors create a small AC current. At 1 revolution per second, the AC voltage from each sensor should be around 0.2 volts.
• To check the sensors and their cables aren't earthing out, measure the resistance between pin 1 and pins 4, 5, 6 and 7 - should be infinite. The cables are shielded co-axial cable, so if the sheath has worn through, a sensor may be earthing.
• Check the earth connection - meter 11 and 1 for resistance - should be 0 ohms.
• Measure resistance for these pairs to check sensor resistance: 4 & 22, 5 & 23, 6 & 24, 7 & 25. Should be within the tolerance noted above
• To meaure the resistance of the valve block solenoids, measure the resistance between pin 11 (earth) and pins 15, 17 and 35 for the inlets, and between pin 11 and 33, 16 and 34 for the outlets. Tolerances noted above.

Hope some of that helps...