ABS off car

BMW E28 5 series ABS Module

Thinking about ABS repairs.

There are many misconceptions about ABS systems should be robust and simple and the Module/controller/ECU almost never giving any trouble...

Below are some possible causes for damaging an ECU :
Spiked by careless welding i.e. MIG welding without disconnecting the battery. TRUE
Enclosure seal damaged and with obvious sign of water ingress. TRUE
Obvious signs of mechanical damage to the enclosure. TRUE
Often the ECU will be diagnosed as faulty , usually because the technician is inexperienced in faultfinding. TRUE
Faults are much more likely to be with a connections or sensors. TRUE

Below are some practices to help us in diagnostic practices when testing an ABS system :

- Becarefull when working close or near an ECU.
- Always start with the easiest options that we can eliminate first .
- The concept of "Voltdropping" or checking for volt drops on the ground connections and wires and other connections comes in handy .
- Checking sensors if they are working in their expected parameters or manufacturer specs.
- Changing the ECU/Module/Controller should be the last resort or option.

Damaged ECU