SPN 3663/FMI 14
This diagnosis is typically an open circuit, short to ground or short to power.
Check as follows:
- Check for multiple codes.
- If fault code 168/1 is active, service 168/1 first.
- If fault 3662/14 and 3664/14 are active in addition to 3663/14, go to the next step.
- If only fault code 3663/14 is active, go to step 10 .
- Turn the ignition OFF.
- Disconnect the Rear Injector Harness 14–pin connector.
- Inspect the Rear Injector Harness 14–pin connector for bent or spread pins. Inspect the connector seal for damage (signs of water or oil intrusion).
- If water or oil intrusion, bent or spread pins are found, repair as necessary. Refer to “125.1.1 Verify Repairs” .
- If connector shows no signs of damage, go to the next step.
- Measure the resistance between pin 5 and pin 9 on the valve cover side of the injector harness. If using J-48671–10 , measure between injector #5 pins 1 and 2.
- If the resistance is greater than 3 Ω, replace the under valve cover injector harness. Refer to “125.1.1 Verify Repairs” .
- If the resistance is less than 3 Ω, go to the next step.
- Disconnect the MCM 120–pin connector.
- Measure the resistance between pin 7 of the MCM 120–pin connector and pin 5 of the Rear Injector Harness 14–pin connector.
- If the resistance is greater than 3 Ω, repair the open between pin 7 of the MCM 120–pin connector and pin 5 of the Rear Injector Harness 14–pin connector. Refer to “125.1.1 Verify Repairs” .
- If the resistance is less than 3 Ω, go to the next step.
- Disconnect the negative battery cable.
- Measure the resistance between the positive battery post and pin 7 of the MCM 120–pin connector.
- If the resistance is less than 3 Ω, repair the short to power between battery positive and pin 7 of the 120–pin MCM connector. Refer to “125.1.1 Verify Repairs” .
- If the resistance is greater than 3 Ω, contact the Detroit Diesel Customer Support Center at 313–592–5800 for MCM replacement authorization.
- Turn the ignition OFF.
- Disconnect the Rear Injector Harness 14–pin connector.
- Measure the resistance between pin 5 and pin 9 on the valve cover side of the injector harness. If using J-48671–10 , measure between injector #5 pins 1 and 2.
- If the resistance is greater than 3 Ω, go to step 18 .
- If the resistance is less than 3 Ω, go to the next step.
- Remove the upper valve cover.
- Disconnect injector #5.
- Measure the resistance between pin 5 on the valve cover side of the Rear Injector Harness and pin 1 on the injector #5 harness connector. If using J-48671–10 , measure between injector #5 pin 1 and pin 1 on the injector #5 harness connector.
- If the resistance is greater than 3 Ω, replace the under valve cover injector harness. Refer to “125.1.1 Verify Repairs” .
- If the resistance is less than 3 Ω, go to the next step.
- Measure the resistance between pin 9 on the valve cover side of the Rear Injector Harness and pin 2 of the injector #5 harness connector. If using J-48671–10 , measure between injector #5 pin 2 and the injector #5 harness connector pin 2.
- If the resistance is greater than 3 Ω, replace the under valve cover injector harness. Refer to “125.1.1 Verify Repairs” .
- If the resistance is less than 3 Ω, go to the next step.
- Measure the resistance between pin 9 on the valve cover side of the Rear Injector Harness and ground. If using J-48671–10 , measure between injector #5 pin 2 and ground.
- If the resistance is less than 3 Ω, replace the under valve cover injector harness. Refer to “125.1.1 Verify Repairs” .
- If the resistance is greater than 3 Ω, replace injector #5. Refer to “125.1.1 Verify Repairs” .
- Measure the resistance between pin 9 on the valve cover side of the Rear Injector Harness and ground. If using J-48671–10 , measure between injector #5 pin 2 and ground.
- If the resistance is less than 3 Ω, go to the next step.
- If the resistance is greater than 3 Ω, repair the short to ground between pin 4 of the MCM 120–pin connector and pin 9 of the Rear Injector Harness connector. Refer to “125.1.1 Verify Repairs” .
- Remove the upper valve cover.
- Disconnect injector #5 connector.
- Measure the resistance between pin 9 on the valve cover side of the Rear Injector Harness and ground. If using J-48671–10 , measure between injector #5 pin 2 and ground.
- If the resistance is less than 3 Ω, replace the under valve cover injector harness. Refer to “125.1.1 Verify Repairs” .
- If the resistance is greater than 3 Ω, replace injector #5. Refer to “125.1.1 Verify Repairs” .
Verify Repairs
Verify repairs as follows:
- Turn ignition OFF.
- Reconnect any electrical connections that were disconnected to perform the diagnosis.
- Clear codes with DDDL 7.0 or latest version.
ENGINE EXHAUST To avoid injury from inhaling engine exhaust, always operate the engine in a well-ventilated area. Engine exhaust is toxic. - Start and bring engine up to operating temperature (over 140°F/60°C).
- Verify operation is satisfactory and no warning lamps illuminate. If warning lamps illuminate, troubleshoot the codes.