ML4 - Check For B+ at MIL Bulb/Socket
- Key "ON", engine "OFF".- Measure voltage from battery negative post to B+ side of Malfunction Indicator Light (MIL) bulb/socket.
- Is voltage greater than 10.5 volts?
Yes -- Go to ML5. ML5 - Check MIL Bulb Response to Grounding
No -- Service open between MIL fuse and MIL bulb. Verify service by turning ignition key to "Run" position.