DTC 26

CIRCUIT OPERATION
- Battery positive voltage is supplied to the stoplight switch (terminal 2).
- When the brake pedal is depressed, battery positive voltage is applied to the PCM (terminal 123). The PCM judges that the brake pedal is depressed and the stoplight switch is on when battery positive voltage is sensed at the PCM (terminal 123).

DTC SET CONDITIONS
- If the stoplight switch is on for five minutes or more while driving 50 km/h (31 mph), it is judged there is a short circuit in the stoplight switch and diagnostic trouble code number "26" is output.

TROUBLESHOOTING HINTS
The most likely causes for this code to be set:
- Malfunction of the stoplight switch circuit
- Damaged harness, connector
- Malfunction of the PCM

DIAGNOSIS





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

CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.

STEP 1. Using Scan Tool MB991502, Check Data List Item 26: Stoplight Switch.
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Set scan tool MB991502 to the data reading mode for item 26, Stoplight switch.
4. When the brake pedal is depressed, the display should be "ON."
5. When the brake pedal is not depressed, the display should be "OFF."
If the stoplight switch is operating properly, this malfunction may be intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.
If the stoplight switch is not operating properly, go to Step 2.

STEP 2. Check That The Stoplight Illuminates.
The stoplight should illuminate when the brake pedal is depressed.
If the stoplight does not illuminates, go to Step 3.
If the stoplight illuminates, go to Step 7.

STEP 3. Check The Stoplight Switch.
Check the stoplight switch. Refer to On-vehicle Service - Stoplight Switch Check.
If detective, replace the stoplight switch. Refer to Brake Pedal.
If not defective, go to Step 4.

STEP 4. Check The Power Supply Circuit At The Stoplight Switch.





1. Disconnect harness connector C-03 and measure at the harness side.
2. Measure the voltage between terminal 2 and ground.
- Voltage should be battery positive voltage.
If not battery positive voltage, repair the connectors or the harness wires between the stoplight switch and fusible link (2).
If battery positive voltage, go to Step 5.

STEP 5. Check Harness Connector C-03 At The Stoplight Switch For Damage.





If harness connector C-03 is damaged, repair or replace it. Refer to Harness Connector Inspection. Recheck for DTCs.
If harness connector C-03 is in good condition, go to Step 6.

STEP 6. Check Harness Connector C-90 At The Intermediate Connector For Damage.





If harness connector C-90 is damaged, repair or replace it. Refer to Harness Connector Inspection. Recheck for DTCs.
If harness connector C-90 is in good condition, repair the connectors or the harness wires between the stoplight switch and the intermediate connector.

STEP 7. Check Harness Connector C-61 <2.4L Engine> Or C-63 <3.0L Engine> At The PCM For Damage.





If harness connector C-61 <2.4L Engine> or C-63 <3.0L Engine> is damaged, repair or replace it. Refer to Harness Connector Inspection. Recheck for DTCs.
If harness connector C-61 <2.4L Engine> or C-63 <3.0L Engine> is in good condition, go to Step 8.

STEP 8. Measure The PCM Terminal Voltage.
Measure the voltage at terminal 123 of PCM connector C-61 <2.4L Engine> or C-63 <3.0L Engine>. Refer to PCM Terminal Voltage Reference Chart for Transaxle Operation.
If the voltage meets the specifications, replace the PCM. The immobilizer-ECU and the ignition key should be replaced together with it. Refer to Ignition Switch and Immobilizer System - Ignition Switch and Immobilizer System.
If the voltage does not meet the specification, repair the connectors or the harness wires between the stoplight switch and the PCM.