5-11
BF135A•BF150A
5. TROUBLESHOOTING
The ECM (Engine Control Module) has the self-diagnosis
function which memorizes the failure code and turns the
MIL (Malfunction Indicator Light) ON when it detects an
abnormality with the input/output system.
• If the MIL does not come ON but the engine failure
(abnormality other than monitoring ECM) occurred,
detect the probable problem part by referring to the
Quick Reference Chart of Troubleshooting by System on
page 5-12, and troubleshoot accordingly.
• HOW TO CARRY OUT TROUBLESHOOTING
When the MIL comes ON or blinks or any abnormality
occurs during running, identify the problem detected by
ECM according to the following procedure, and trou-
bleshoot accordingly.
To troubleshoot, connect the tester probe to a commer-
cially available digital circuit tester. Note that the tester
probe must agree with the connector terminal of the digi-
tal circuit tester not to apply excessive force to the con-
nector terminal.
1. Turn the ignition switch ON and check that the MIL
comes ON.
2. When the MIL is ON or blinking, check the DTC
(Diagnostic Trouble Code) using the HDS tester (P. 5-
13).
Or, use the short connector to blink the MIL and trou-
bleshoot the problem indicated by the number of blinks
of the MIL (P. 5-57).
3. Perform the troubleshooting by referring to the “Trou-
bleshooting Guide by DTC” (P. 5-15) or “Troubleshoot-
ing Guide by No. of Blinks” (P. 5-59).
Check each connector and wire harness for secure
connection and damage before troubleshooting.
Repair the connector and wire harness if necessary.
4. After troubleshooting, perform repairs as needed and
perform the necessary work (P. 5-14 or 5-58).
PGM-FI MIL
