Long story short, I removed engine and gearbox, the only thing on the brakes I disturbed was removal of front calipers, which I plugged the pipe's and re-bled on fitting.

At first road test I had the pedal jumping back at me from 10-0mph only. The red light and abs yellow light would come on.

I've fiddled about with the wires and float, the switch seems to work good. The pump primes and clicks of once under pressure.

I have swapped the ABS ECU for a spare, results are the same. I have ran 1 litre of brake fluid through front and rear calipers, all is good and clear.

Now the red light (low pressure) no longer comes on when driving but the yellow abs light comes on at random and goes out at random. The pedal has a normal feel, I've covered 128 miles with no further issue.

1. what is the resistance between terminals 11 and 18 (ECU unplugged, ignition off) ? 004
2. what is the resistance between terminals 11 and 1 (ECU unplugged, ignition off) ? 0
3. what is the resistance between terminals 11 and 15 (ECU unplugged, ignition off) ? 005
4. what is the resistance between terminals 11 and 16 (ECU unplugged, ignition off) ? 003
5. what is the resistance between terminals 11 and 17 (ECU unplugged, ignition off) ? 006
6. what is the resistance between terminals 11 and 18 (ECU unplugged, ignition off) ? 003
7. what is the resistance between terminals 11 and 33 (ECU unplugged, ignition off) ? 003
8. what is the resistance between terminals 11 and 34 (ECU unplugged, ignition off) ? 003
9. what is the resistance between terminal 9 and earth (ECU unplugged, ignition off) ? 1
10. what is the resistance between terminal 10 and earth (ECU unplugged, ignition off) ? 1
11. what is the resistance between terminals 1 and 3 (ECU unplugged, ignition off) ? 000
12. what is the resistance between terminals 1 and 20 (ECU unplugged, ignition off) ? 000
13. what is the resistance between terminals 1 and 8 (ECU unplugged, ignition off) ? 068
14. what is the voltage between terminals 1 and 2 (ECU unplugged, ignition on) ? 12.12v
15. with ECU unplugged and ignition off, temporarily join terminals 2 and 8 with a jumper wire. With ignition on, what is the voltage between terminals 1 and 3 = 12.28v and 1 and 20 = 12.17v

RH rear sensor : Connect ohmmeter between terminals 4 and 1 of ECU. Infinity
LH rear sensor : Connect ohmmeter between terminals 6 and 1 of ECU. Infinity
RH front sensor : Connect ohmmeter between terminals 7 and 1 of ECU. Infinity
LH front sensor : Connect ohmmeter between terminals 5 and 1 of ECU. Infinity

All sensors show 1050 - 1100ohms resistance
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