INPUT SIGNAL PROCEDURES
TSB Revision
SIMPLIFIED WIRING SYSTEM (SWS)
54B-529
STEP 2. Replace the ECU.
(1) Replace the column switch (lighting and turn-signal light
switch).
(2) If the functions, which are described in "CIRCUIT
OPERATION", work normally, the input signal from the
column switch (lighting and turn-signal light switch) should
be normal.
Q: Does the column switch (lighting and turn-signal light
switch) send normal signal to the ECU?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. If the functions, which are
described in "CIRCUIT OPERATION", work normally,
the input signal from the column switch (lighting and
turn-signal light switch) should be normal.
INSPECTION PROCEDURE O-7: Column Switch: ETACS-ECU does not receive any signal from
windshield mist wiper switch, windshield intermittent wiper switch, windshield low-speed wiper
switch, windshield high-speed wiper switch, windshield washer switch, rear wiper switch or rear
washer switch.
NOTE: This troubleshooting procedure requires the
use of scan tool MB991958 and SWS monitor kit
MB991862. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor
P.54B-10
."
.
CIRCUIT OPERATION
The ETACS-ECU operates the following equipment
according to signal from the column switch (wind-
shield wiper and washer switch):
• Windshield wiper and washer
• Rear wiper and washer
.
Windshield Wiper and Washer Switch Input Circuit