DTC 56
DTC 56: "N" Range Light System Vehicles with sport modesCIRCUIT OPERATION
If a fail-safe is triggered while driving forward, the PCM flashes the "N" range light once per second (triggered fail-safe). The PCM does this by switching battery positive voltage to terminal 121.
DTC SET CONDITIONS
If the PCM detects a fail-safe condition, it will attempt to illuminate the "N" range light. The PCM sends a 12 volts pulse for 60 - 180 ms. If it does not detect a voltage drop during the pulse, it waits about 60 seconds and pulses 12 volts again for 60 - 180 ms. If the PCM does no detect the voltage drop before the ignition switch is turned "LOCK" (OFF), the PCM will consider it as a short circuit of the "N" range light circuit and output code number "56."
TROUBLESHOOTING HINTS (The most likely causes for this code to be set:)
- Defective "N" range light bulb
- Damaged harness, connector
- Malfunction of the PCM.
DIAGNOSIS
Required Special Tool:
- MB991502: Scan Tool (MUT-II)
CAUTIONS: To prevent damage to the scan tool MB991502, always turn the ignition switch to the "LOCK"(OFF) position before connecting or disconnecting the scan tool MB991502.
STEP 1. Using scan tool MB991502, check the light bulb.
1) Connect scan tool MB991502 to the data link connector.
2) Turn the ignition switch to the "ON" position.
- The "N" range light in the combination meter flushes.
3) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Does the "N" range light flush?
YES: This malfunction is intermittent.
NO: Go to Step 2.
STEP 2. Check the "N" range light bulb.
1) Remove the combination meter.
2) Check the "N" range light bulb.
Q: Is the valve in good condition?
YES: Go to Step 3.
NO: Replace the bulb.
STEP 3. Check connectors C-103 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Go to Step 4.
NO: Repair or replace it.
STEP 4. Check the continuity at combination meter connector C-103.
1) Disconnect connector C-103 and measure at the harness side.
2) Check for the continuity between terminal 12 and ground.
- Should be less than 2 ohm.
Q: Is the continuity normal?
YES: Go to Step 6.
NO: Go to Step 5.
STEP 5. Check connector C-103 at combination meter for damage.
Q: Is the connector in good condition?
YES: Repair it because of harness open circuit or harness damage between combination meter connector C-103 terminal 12 and the ground.
NO: Repair or replace it.
STEP 6. Check connectors C-123 at PCM, C-24 at intermediate connector, B-111 Park/Neutral position switch connector and C-103 at combination meter for damage.
Q: Are the connectors in good condition?
YES: Go to Step 7.
NO: Repair or replace it.
STEP 7. Check harness for open circuit, short circuit to ground and damage between combination meter connector C-103 terminal 9 and PCM connector C-123 terminal 121.
Q: Is the harness wire in good condition?
YES: Go to Step 8.
NO: Repair or replace it.
STEP 8. Check harness for damage between combination meter connector C-103 terminal 12 and the ground.
Q: Is the harness wire in good condition?
YES: Go to Step 9.
NO: Repair or replace it.
STEP 9. Check connector B-111 at Park/Neutral position switch for damage.
Q: Is the connector in good condition?
YES: Go to Step 10.
NO: Repair or replace it.
STEP 10. Check harness for short circuit to ground between combination meter connector C-103 terminal 9 and Park/Neutral position switch connector E1-111 terminal 4.
Q: Is the harness wire in good condition?
YES: Go to Step 11.
NO: Repair or replace it.
STEP 11. Using scan tool MB991502, check the light bulb.
CAUTION: To prevent damage to the scan tool MB991502, always turn the ignition switch to the "LOCK"(OFF) position before connecting or disconnecting the scan tool MB991502.
1) Connect scan tool MB991502 to the data link connector.
2) Turn the ignition switch to the "ON" position.
- The "N" range light in the combination meter flushes.
3) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Does the "N" range light flush?
YES: This malfunction is intermittent.
NO: Replace the PCM.