While in Test Mode 1, turn off the MPCS short connector switch (A) for about 5 to 10 seconds, then turn it on again.
The ceiling light should come on for 2 seconds, go out, then blinks twice more at 0.2 second intervals. This means the system has gone from Test Mode 1 to Test Mode 2.
While still in Test Mode 2, operate the switches in the table below. If the circuit is OK, the ceiling light blinks once. If the circuit is faulty, the ceiling light does not blink.
If the ceiling light does not blink even a switch is operated, check two or three other circuits listed in the table. If the ceiling light blinks for each circuit, the additional circuits are OK, repair the short or open circuit that failed the test in
Step 3
.
If the ceiling light does not blink again, this multiple failed circuits mean that the control unit has failed without triggering a DTC. Test a few more circuits. If they also fail,
test the MICU input test,
or the
gauge control module self-diagnosis function.
If all the tests prove OK, substitute a known-good MICU or gauge control module (tach) one at a time, then recheck. If the system works properly, the part that was substituted is faulty; replace it.
Driver's door lock switch (UNLOCK)
Windshield wiper MIST switch
Driver's door lock switch (LOCK)
Windshield washer switch
Driver's door lock knob switch (UNLOCK)
Windshield wiper intermittent dwell time controller