DTC 15
DTC15 : Auto-cruise Control Switch SystemAuto-cruise Control Switch System Circuit Part 1:
Auto-cruise Control Switch System Circuit Part 2:
CIRCUIT OPERATION
This circuit judges the signals of each switch ("OFF," "SET," "RESUME," "CANCEL" and "MAIN") of the auto-cruise control switch. The auto-cruise control-ECU detects the state of the auto-cruise control switch by sensing the voltages shown.
- When all switches are OFF, the ECU detects 3.5 - 5.0 volts.
- When the "SET" switch is ON, the ECU detects 0.4 - 2.3 volts.
- When the "RESUME" switch is ON, the ECU detects 2.3 - 3.5 volts.
- When the "CANCEL" switch is ON, the ECU detects 0.4 volts or less.
- When the main switch is ON, the ECU detects 7.0 volts.
DTC SET CONDITIONS
This code is set when the auto-cruise control switch "RESUME" switch, "SET" switch or "CANCEL" switch stays ON.
TROUBLESHOOTING HINTS
The most likely causes for this code to be set are:
- Malfunction of the auto-cruise control switch.
- Malfunction of the clock spring.
- Damaged harness or connector.
- Malfunction of the auto-cruise control-ECU
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Measure the 12-Volt supply circuit voltage at auto-cruise control switch connector C-202.
1. Disconnect auto-cruise control switch connector C-202. (2) Turn the ignition switch to the "ON" position.
3. Measure the voltage between auto-cruise control switch connector C-202 terminal 1 and ground.
- The measured voltage should measure battery positive voltage.
4. Turn the ignition switch to the "LOCK" (OFF) position, connect auto-cruise control switch connector C-202.
Q: Is the measured voltage battery positive voltage?
YES: Go to Step 6.
NO: Go to Step 2.
STEP 2. Check auto-cruise control switch connector C-202 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connector and terminals in good condition?
YES: Go to Step 3.
NO: Repair or replace connector. Then check that diagnostic trouble code 15 is not set.
STEP 3. Check the clock spring.
Refer to , Air Bag Modules and Clock Spring.
Q: Is the clock spring in good condition?
YES: Go to Step 4.
NO: Replace the clock spring. Then check that diagnostic trouble code 15 is not set.
STEP 4. Check intermediate connector C-229-1, clock spring connectors C-204 and C-229 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 5.
NO: Repair or replace connector. Then check that diagnostic trouble code 15 is not set.
STEP 5. Check the harness wire between junction block (fuse 2) and auto-cruise control switch connector C-202 terminal 1 for damage.
Q: Is the harness wire in good condition?
YES: This malfunction is intermittent. Then check that diagnostic trouble code 15 is not set.
NO: Repair harness wire and then check that diagnostic trouble code 15 is not set.
STEP 6. Measure the signal voltage at auto-cruise control switch connector C-202 by backprobing.
1. Do not disconnect auto-cruise control switch connector C-202.
2. Turn the ignition switch to the "ON" position.
3. Measure the voltage between terminal 2 and ground by backprobing.
- Voltage should measure between 6.8 and 7.2 volts. (MAIN switch is at the "ON" position.)
- Voltage should measure between 3.5 and 5.0 volts. (All switches are at the "OFF" position.)
- Voltage should measure between 0.4 and 2.3 volts. ("SET" switch is at the "ON" position)
- Voltage should measure between 2.3 and 3.5 volts. ("RESUME" switch is at the "ON" position.)
- Voltage should measure between 1 volt or less. ("CANCEL" switch is at the "ON" position.)
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Are all of the measured voltages satisfied?
YES: Go to Step 9.
NO: Go to Step 7.
STEP 7. Check auto-cruise control switch connector C-202 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connector and terminals in good condition?
YES: Go to Step 8.
NO: Repair or replace connector. Then check that diagnostic trouble code 15 is not set.
STEP 8. Check the auto-cruise control switch.
1. Remove the auto-cruise control switch.
2. Measure the resistance between the terminals when each of the "CRUISE" (MAIN), "COAST/SET", "ACC/RES" and "CANCEL" switch is pressed.
Q: Is the measured values correspond to those in the table?
YES: Check that diagnostic trouble code 15 is not set. If diagnostic trouble code 15 is set, replace the auto-cruise control-ECU Then check that diagnostic trouble code 15 is not set.
NO: Replace the auto-cruise control switch. Then check that diagnostic trouble code 15 is not set.
STEP 9. Measure the signal voltage at auto-cruise control-ECU connector C-107 by backprobing.
1. Remove the auto-cruise control-ECU mounting nut.
2. Do not disconnect auto-cruise control-ECU connector C-107.
3. Turn the ignition switch to the "ON" position.
4. Measure the voltage between auto-cruise control-ECU connector C-107 terminal 12 and ground by backprobing.
- Voltage should measure between 6.8 and 7.2 volts. (MAIN switch is at the "ON" position.)
- Voltage should measure between 3.5 and 5.0 volts. (All switches are at the "OFF" position.)
- Voltage should measure between 0.4 and 2.3 volts. ("SET" switch is at the "ON" position.)
- Voltage should measure between 2.3 and 3.5 volts. ("RESUME" switch is at the "ON" position.)
- Voltage should measure between 1 volt or less. ("CANCEL" switch is at the "ON" position.
5. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Are all of the measured voltages satisfied?
YES: Check that diagnostic trouble code 15 is not set. If diagnostic trouble code 15 is set, replace the auto-cruise control-ECU. Then check that diagnostic trouble code 15 is not set.
NO: Go to Step 10.
STEP 10. Check auto-cruise control-ECU connector C-107 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connector and terminals in good condition?
YES: Go to Step 11.
NO: Repair or replace connector. Then check that diagnostic trouble code 15 is not set.
STEP 11. Check the clock spring.
Refer to, Air Bag Modules and Clock Spring.
Q: Is the clock spring in good condition?
YES: Go to Step 12.
NO: Replace the clock spring. Then check that diagnostic trouble code 15 is not set.
STEP 12. Check auto-cruise control switch connector C-202, intermediate connector C-229-1 and C-108 and clock spring connectors C-204 and C-229 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?
YES: Go to Step 13.
NO: Repair or replace connector. Then check that diagnostic trouble code 15 is not set.
STEP 13. Check the harness wires between auto-cruise control switch connector C-202 terminal 2, 3 and auto-cruise control-ECU connector C-107 terminal 12, 9 for damage.
Q: Are the harness wires in good condition?
YES: Check that diagnostic trouble code 15 is not set. If diagnostic trouble code 15 is set, replace the auto-cruise control-ECU. Then check that diagnostic trouble code 15 is not set.
NO: Repair harness wire and then check that diagnostic trouble code 15 is not set.