DTC 16

DTC 16: A/T Fluid Temperature Sensor System (Short Circuit)

A/T Fluid Temperature Sensor System Circuit
Refer to DTC 15.

CIRCUIT OPERATION
Refer to DTC 15.

DTC SET CONDITIONS
If the A/T fluid temperature sensor output detects the voltage which corresponds to 0 volt for more than one second, there is a short in the A/T fluid temperature sensor circuit and DTC 16 is set.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Malfunction of the A/T fluid temperature sensor circuit
- Damaged harness or connector
- Malfunction of the PCM

DIAGNOSIS

Required Special Tool:
- MB991502: Scan Tool (MUT-II)

STEP 1. Using scan tool M13991502, check data list item 15: A/T Fluid Temperature Sensor.

CAUTION: To prevent damage to scan tool M13991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool M13991502.

1) Do not disconnect connector B-110.
2) Turn the ignition switch to the "ON" position.

3) Measure the voltage between terminal 1 and ground by backprobing.
- When A/T fluid temperature is 20 °C (68 °F), voltage should measure between 3.8 and 4.0 volts.
- When A/T fluid temperature is 40 °C (104 °F), voltage should measure between 3.2 and 3.4 volts.
- When A/T fluid temperature is 80 °C (176 °F), voltage should measure between 1.7 and 1.9 volts.

4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage within the specified range?
YES: Go to Step 6.
NO: Go to Step 3.

STEP 3. Check A/T control solenoid valve assembly connector B-110 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 4.
NO: Repair or replace the damaged components.

STEP 4. Check the sensor output voltage at A/T control solenoid valve assembly connector B-110.

1) Disconnect connector B-110 and measure at the harness side.
2) Turn the ignition switch to the "ON" position.

3) Measure the voltage between terminal 1 and ground.
- The voltage should measure between 4.5 and 4.9 Volts.

4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage between 4.5 and 4.9 volts?
YES: Go to Step 5.
NO: Go to Step 7.

STEP 5. Check the A/T fluid temperature sensor at A/T control solenoid valve assembly connector B-110.

1) Disconnect connector B-110 and measure at the sensor side.

2) Measure the resistance between terminal 1 and 2.
- When A/T fluid temperature is 0 °C (32 °F), resistance should be between 16.7 and 20.5 K ohms.
- When A/T fluid temperature is 20 °C (68 °F), resistance should be between 7.3 and 8.9 K ohms.
- When A/T fluid temperature is 40 °C (104 °F), resistance should be between 3.4 and 4.2 K ohms.
- When A/T fluid temperature is 60 °C (140 °F), resistance should be between 1.9 and 2.2 K ohms.
- When A/T fluid temperature is 80 °C (176 °F), resistance should be between 1.0 and 1.2 K ohms.
- When A/T fluid temperature is 100 °C (212 °F), resistance should be between 0.57 and 0.69 K ohms.

Q: Is the measured resistance within the specified range?
YES: Go to Step 6.
NO: Replace the A/T fluid temperature sensor.

STEP 6. Using scan tool M13991502, check data list item 15: A/T Fluid Temperature Sensor.

CAUTION: To prevent damage to scan tool M13991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool M13991502.

1) Connect scan tool MB991502 to the data link connector.
2) Start the engine.
3) Set scan tool MB991502 to data reading mode for item 15, A/T Fluid Temperature Sensor.
- When the engine is cool: Almost equal to the ambient temperature (atmospheric temperature)

NOTE: Set scan too/ MB991502 to data reading mode for item number 13, Intake Air Temperature (IAT) Sensor and note the temperature measurement. When the engine is cool, the temperature should be almost equal to the ambient temperature (atmospheric temperature), and the IAT sensor measurement should be approximately the same as the A/T Fluid Temperature Sensor

- When the engine is warm: 70 to 80 °C (158 to 176 °F)

4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the sensor operating properly?
YES: It can be assumed that this malfunction is intermittent.
NO: Replace the PCM.

STEP 7. Measure the sensor output voltage at PCM connector C-121 <2.41L Engine> or C-123 <3.0L Engine> by backprobing.

1) Do not disconnect connector C-121 <2.4L Engine> or C123 <3.0L Engine>.
2) Turn the ignition switch to the "ON" position.

3) Measure the voltage between terminal 124 and ground by backprobing.
- When A/T fluid temperature is 20 °C (68 °F), voltage should measure between 3.8 and 4.0 volts.
- When A/T fluid temperature is 40 °C (104 °F), voltage should measure between 3.2 and 3.4 volts.
- When A/T fluid temperature is 80 °C (176 °F), voltage should measure between 1.7 and 1.9 volts.

4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage within the specified range?
YES: Go to Step 6.
NO: Go to Step 8.

STEP 8. Check PCM connector C-121 <2.4L Engine> or C123 <3.0L Engine> 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 9.
NO: Repair or replace the damaged components.

STEP 9. Check the harness for a short circuit to ground between A/T control solenoid valve connector B-110 terminal 1 and PCM connector C-121 <2.4L Engine> or C123 <3.0L Engine> terminal 124.

Q: Is the harness wire in good condition?
YES: Go to Step 6.
NO: Repair or replace the harness wire.