DTC 34
DTC 34: Overdrive Solenoid Valve System
Solenoid Valve System Circuit
CIRCUIT OPERATION
- A/T control relay supplies battery positive voltage to each solenoid valve (terminal 9 and 10).
- Solenoid valve closes when energized (on), and opens when deenergized (off). The PCM energize or deenergize solenoid valve, based on inputs data from sensors such as Throttle Position Sensor, Park/Neutral Position Switch, Stoplight Switch, Vehicle Speed Sensor, Input Shaft Speed Sensor, Output Shaft Speed Sensor, A/T Fluid Temperature Sensor etc.
- The PCM provides the ground to energize solenoid. The ground time is displayed in percent.
- As solenoid is energized or deenergized, it influences hydraulic pressure in the transmission applying and releasing elements.
DTC SET CONDITIONS
If the resistance value for a solenoid valve circuit is greater than 3.5 Ohms for 4 seconds at 100°C (212°F) or less than 2.6 Ohms for 4 seconds at 100°C (212°F), it is judged that there is a short circuit or an open circuit in the solenoid valve and the diagnostic trouble code number "34" is displayed. The transmission is locked into 3rd gear as a fail-safe measure.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set:)
- Malfunction of underdrive solenoid valve
- Damaged harness, connector
- Malfunction of the PCM
DIAGNOSIS
Required Special Tool: MB991502: Scan Tool (MUT-II)
STEP 1. Using scan tool MB991502, read the A/T diagnostic trouble code.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Read the A/T diagnostic trouble code.
4. Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the A/T diagnostic trouble code number "54" output?
YES: Refer to code number 54: A/T control relay system.
NO: Go to Step 2.
STEP 2. Using scan tool MB991502, check actuator test item 04: Overdrive Solenoid Valve.
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Set scan tool MB991502 to actuator test mode for item 04, Overdrive Solenoid Valve. An operation sound should be heard from solenoid valve when the overdrive solenoid valve is operated.
4. Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the solenoid valve operating properly?
YES: This malfunction is intermittent. Refer to "General Electrical Troubleshooting".
NO: Go to Step 3.
STEP 3. Check the solenoid valve output voltage at PCM connector C-42 by backprobing.
1. Do not disconnect connector C-42.
2. Turn the ignition switch to "ON" position.
3. Measure the voltage between terminal 130 and ground by backprobing.
- Voltage should be battery positive voltage.
4. Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the voltage normal?
YES: Go to Step 4.
NO: Go to Step 9.
STEP 4. Check connectors B-38 at solenoid valve assembly and C-42 at PCM for damage.
Q: Are the connectors in good condition?
YES: Go to Step 5.
NO: Repair or replace it.
STEP 5. Check harness for damage between solenoid valve assembly connector B-38 terminal 5 and PCM connector C-42 terminal 130.
Q: Is the harness wire in good condition?
YES: Go to Step 6.
NO: Repair it.
STEP 6. Check connector A-19X at A/T control relay for damage.
Q: Is the connector in good condition?
YES: Go to Step 7.
NO: Repair or replace it.
STEP 7. Check harness for damage between solenoid valve assembly connector B-38 terminal 9 and A/T control relay connector A-19X terminal 3.
Q: Is the harness wire in good condition?
YES: Go to Step 8.
NO: Repair it.
STEP 8. Using scan tool MB991502, check actuator test item 04: Overdrive Solenoid Valve.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to data link connector.
2. Turn the ignition switch to "ON" position.
3. Set scan tool MB991502 to the actuator test mode for item 04: Overdrive Solenoid Valve. An operation sound should be heard from solenoid valve when the overdrive solenoid valve is operated.
4. Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the solenoid valve operating properly?
YES: This malfunction is intermittent. Refer to "General Electrical Troubleshooting".
NO: Replace the PCM.
STEP 9. Check connector B-38 at solenoid valve assembly for damage.
Q: Is the connector in good condition?
YES: Go to Step 10.
NO: Repair or replace it.
STEP 10. Check the overdrive solenoid valve at solenoid valve assembly connector B-38.
1. Disconnect connector B-38 and measure at the solenoid valve side.
2. Measure the resistance between terminal 5 and 9.
Standard value: 2.7 - 3.4 ohms
Q: Is the resistance at the standard value?
YES: Go to Step 11.
NO: Replace the overdrive solenoid valve.
STEP 11. Check the power supply voltage at solenoid valve assembly connector B-38.
1. Disconnect connector B-38 and measure at the harness side.
2. Turn the ignition switch to "ON" position.
3. Measure the voltage between terminal 9 and ground.
- Voltage should be battery positive voltage.
4. Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the voltage normal?
YES: Go to Step 13.
NO: Go to Step 12.
STEP 12. Check connector A-19X at A/T control relay for damage.
Q: Is the connector in good condition?
YES: Repair it because of harness open circuit or short circuit to ground between solenoid valve assembly connector B-38 terminal 9 and A/T control relay connector A-19X terminal 3.
NO: Repair or replace it.
STEP 13. Check connector C-42 at PCM connector for damage.
Q: Is the connector in good condition?
YES: Go to Step 14.
NO: Repair or replace it.
STEP 14. Check harness for open circuit, or short circuit to ground between solenoid valve assembly connector B-38 terminal 5 and PCM connector C-42 terminal 130.
Q: Is the harness wire in good condition?
YES: Replace the PCM.
NO: Repair it.