LED 4 Does Not Light, Tester In Position 1

Fig. 4 LED Identification:

Fig. 1 ABS Control Unit Connector Terminal Identification:

Fig. 5 Black Hydraulic Modulator Connector Terminal Identification:

Refer to Fig. 4, for LED identification. Weaker illumination of an LED indicates a contact resistance in respective circuit.
1. Check for continuity between ABS control unit connector terminal 32 and black hydraulic modulator connector terminal 12 (LED 4). Figs 1 and 5.
2. If continuity does not exist, repair circuit for short or open.
3. Check for continuity between ABS control unit connector terminal 20 and ground, at battery ground cable.
4. If continuity does not exist, repair circuit for short or open. If terminal 20 is disconnected, battery LED will not be lit.
5. Check for defective ABS On/Off switch, wiring, light bulb and warning light diode. Check warning light diode as follows.
6. Check continuity between black hydraulic modulator connector terminal 10 and ABS control unit terminal 29. Figs. 1 and 5.
7. If continuity does not exist, repair circuit for short or open.
8. Check for continuity and contact resistance, both ways, in the top socket between black hydraulic modulator terminals 10 and 12.
9. Ohmmeter must read continuity in one direction and no continuity in the other. Diode is not replaceable. Black hydraulic modulator must be replaced as a unit.