Inspection Procedure P-12
ETACS-ECU does not Receive Vehicle Speed Signal.Vehicles Speed Signal Input Circuit:
CIRCUIT OPERATION
The ETACS-ECU controls the windshield intermittent wiper interval according to the vehicle speed signal, which the powertrain control module sends.
TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the wiper interval, which is described in "CIRCUIT OPERATION", will not be changed correctly. If the signal is not normal, the powertrain control module or the ETACS-ECU may be defective.
TROUBLESHOOTING HINTS
- Malfunction of the powertrain control module
- Malfunction of the ETACS-ECU
- Damaged harness wipes or connectors
DIAGNOSIS
Required Special Tools:
- MB991223: Test Harness Set
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicles communication interface
- MB991827: MUT-III USB cable
- MB991911: MUT-III Main harness B
STEP 1. Check that the combination meter (speedometer) works normally.
Q: Does the combination meter (speedometer) work normally?
YES: Go to Step 2.
NO: Refer to Inspection Procedure O-8 "ETACS-ECU does not receive a signal from the windshield mist wiper switch."
STEP 2. Check ETACS-ECU connector C-118 and powertrain control module connector C-57 <2.4 L ENGINE> or C-59 <3.0 L ENGINE> for damage.
Q: Are ETACS-ECU connector C-118 and powertrain control module connector C-57 <2.4 L ENGINE> or C-59 <3.0 L ENGINE> in good condition?
YES: Go to Step 3.
NO: Repair or replace the connector. Refer to Harness Connector Inspection. If the wiper interval can be adjusted normally, it indicates that the windshield intermittent wiper interval adjusting knob should send a signal to the ECU.
STEP 3. Check the wiring harness between ETACS-ECU connector C-118 (terminal 63) and powertrain control module connector C-57 (terminal 80) <2.4 L ENGINE> or C-59 (terminal 80) <3.0 L ENGINE>.
NOTE: Also check intermediate connector C-28 and joint connector C-77. If intermediate connector C-28 or joint connector C-77 is damaged, repair or replace the connector as described in Harness Connector Inspection.
Q: Is the wiring harness between ETACS-ECU connector C-118 (terminal 63) and powertrain control module connector C-57 (terminal 80) <2.4 L ENGINE> or C-59 (terminal 80) <3.0 L ENGINE> in good condition?
YES: Replace the ETACS-ECU. If the wiper interval can be adjusted normally, it indicates that the windshield intermittent wiper interval adjusting knob should send a signal to the ECU.
NO: Repair the wiring harness. If the wiper interval can be adjusted normally, it indicates that the windshield intermittent wiper interval adjusting knob should send a signal to the ECU.