03 07-16

1

03 07-16

SUBJECT

DATE

SPN 723 (MCM)

March 2016

Additions, Revisions, or Updates
Publication Number / Title

DDC-SVC-MAN-0084

DDC-SVC-MAN-0191

Platform

Section Title

Change

DD Platform

SPN 723/FMI 31 EPA07 - EPA10 GHG14

Add EGR hot pipe check.

DD Platform
GHG17

SPN 723/FMI 31 GHG17

DiagnosticLink users: Please update the troubleshooting guides in DiagnosticLink with this newest version. To update the
tool troubleshooting guide, open DiagnosticLink and from the Help – Troubleshooting Guides menu, select the appropriate
troubleshooting manual, then click Update.

All information subject to change without notice.

03 07-16

Copyright © 2016 DETROIT DIESEL CORPORATION

3

2 SPN 723/FMI 31 - EPA07 - EPA10 - GHG14

2

SPN 723/FMI 31 - EPA07 - EPA10 - GHG14

Backwards Running Engine Detected
This may be due to an engine temporarily running in a reverse direction. Symptoms include smoke exiting from intake
manifold and a low idle speed, possibly due to a leaky injector.
Table 1.
SPN 723/FMI 31
Description

No Match of Camshaft and Crankshaft Signals

Monitored Parameter

Camshaft Reverse Direction Rising Edge Signal

Typical Enabling Conditions

Engine State and Low Idle and Camshaft Reverse Direction Error

Monitor Sequence

None

Execution Frequency

Continuous When Enabling Conditions Met

Typical Duration

Two Seconds

Dash Lamps

MIL, CEL

Engine Reaction

Derate 25%, Shutdown Priority

Verification

Engine Idle

NOTICE: A reverse rotation of the engine will temporarily affect oil pump output. Oil pressure must be checked
after engine starts. Possible bearing damage may exist.
Check as follows:
1. Check the Motor Control Module (MCM) software level. Compare the current MCM software level to the server. Is the
MCM software at the latest level?
a. Yes; Go to step 2.
b. No; update the MCM software level and perform the verification procedure in the table above. If the fault code
does not return, release the vehicle. If the fault code returns or if unable to duplicate verification cycle, Go to step
2.
2. Inspect the Exhaust Gas Recirculation (EGR) hot pipe for fuel, coolant, or oil.
For the DD13, Refer to section "Cleaning of the DD13 Exhaust Gas Recirculation System"
For the DD15 and DD16, Refer to section "Cleaning of the Turbo Compound DD15 and DD16 Exhaust Gas
Recirculation Systems"
3. Is fuel present in the EGR hot pipe?
a. Yes; fuel is present. Refer to section "Test-E - Two-Filter Fuel System".
b. No; Go to step 4.
4. Is coolant present in the EGR hot pipe?
a. Yes; coolant is present. Pressurize the cooling system according to Original Equipment Manufacturer (OEM)
specifications. Repair as necessary.
b. No; Go to step 5.
5. Is oil present in the EGR hot pipe?
a. Yes; oil is present. Inspect turbocharger inlet and outlet for oil. Repair as necessary.
b. No; reinstall the EGR hot pipe with new sealing gaskets and exhaust clamps. Refer to section "Installation of the
Exhaust Gas Recirculation Hot Pipe". Go to step 6.
6. Turn the ignition ON (key ON, engine OFF).
7. Are there any Camshaft Position (CMP) sensor, Crankshaft Position (CKP) sensor, or oil pressure faults present?
a. Yes; repair those faults first.
b. No; Go to step 8.
8. Are there any throttle pedal or idle validation switch faults present?
a. Yes; repair those faults first.
4

All information subject to change without notice.

Copyright © 2016 DETROIT DIESEL CORPORATION

03 07-16

03 07-16
b. No; Go to step 9.
9. Perform an Idle Speed Balance (ISB) test. Are any faulty fuel injectors identified?
a. Yes; replace suspect fuel injector(s).
b. No; Go to step 10.
10. Use DiagnosticLink ® to insure that cranking speed is over 150 rpm. Is cranking speed over 150 rpm?
a. Yes; Go to step 11.
b. No; determine the cause of low crank speed.
11. Turn the ignition OFF.
12. Has the engine had any gear train, camshaft, or flywheel repairs made?
a. Yes; verify proper gear train timing and proper flywheel installation. Refer to section "Camshaft Timing
Verification".
b. No; Go to step 13.
13. Remove the CMP sensor and inspect for damage. Is there damage to the sensor?
a. Yes; inspect the tone wheel on the intake camshaft for damage. Check gear train for excessive lash or damage. If
damage is found, repair as necessary and replace the camshaft position sensor. Refer to section "Removal of the
Camshaft Position Sensor".
b. No; replace the camshaft position sensor. Refer to section "Removal of the Camshaft Position Sensor".

All information subject to change without notice.

03 07-16

Copyright © 2016 DETROIT DIESEL CORPORATION

5

3 SPN 723/FMI 31 - GHG17

3

SPN 723/FMI 31 - GHG17

Backwards Running Engine Detected
This may be due to an engine temporarily running in a reverse direction. Symptoms include smoke exiting from intake
manifold and a low idle speed, possibly due to a leaky injector.
Table 2.
SPN 723/FMI 31
Description

No Match of Camshaft and Crankshaft Signals

Monitored Parameter

Camshaft Reverse Direction Rising Edge Signal

Typical Enabling Conditions

Engine State and Low Idle and Camshaft Reverse Direction Error

Monitor Sequence

None

Execution Frequency

Continuous When Enabling Conditions Met

Typical Duration

Two Seconds

Dash Lamps

MIL, CEL

Engine Reaction

Derate 25%, Shutdown Priority

Verification

Engine Idle

NOTICE: A reverse rotation of the engine will temporarily affect oil pump output. Oil pressure must be checked
after engine starts. Possible bearing damage may exist.
Check as follows:
1. Inspect the Exhaust Gas Recirculation (EGR) hot pipe for fuel, coolant, or oil.
For the DD13, Refer to section "Cleaning of the DD13 Exhaust Gas Recirculation System"
For the DD15, Refer to section "Cleaning of the DD15 Exhaust Gas Recirculation System"
For the DD16, Refer to section "Cleaning of the DD16 Exhaust Gas Recirculation System"
2. Is fuel, coolant, or oil present in the EGR hot pipe?
a. Yes; fuel is present. Refer to section "Test-E - Two-Filter Fuel System".
b. No; Go to step 3.
3. Is coolant present in the EGR hot pipe?
a. Yes; coolant is present. Pressurize the cooling system according to Original Equipment Manufacturer (OEM)
specifications. Repair as necessary.
b. No; Go to step 4.
4. Is oil present in the EGR hot pipe?
a. Yes; oil is present. Inspect turbocharger inlet and outlet for oil. Repair as necessary.
b. No; reinstall the EGR hot pipe with new sealing gaskets and exhaust clamps. Refer to section "Installation of the
Exhaust Gas Recirculation Hot Pipe". Go to step 5.
5. Turn the ignition ON (key ON, engine OFF).
6. Are there any Camshaft Position (CMP) sensor, Crankshaft Position (CKP) sensor, or oil pressure faults present?
a. Yes; repair those faults first.
b. No; Go to step 7.
7. Are there any throttle pedal or idle validation switch faults present?
a. Yes; repair those faults first.
b. No; Go to step 8.
8. Perform an Idle Speed Balance (ISB) test. Are any faulty fuel injectors identified?
a. Yes; replace suspect fuel injector(s).
b. No; Go to step 9.
9. Use DiagnosticLink ® to insure that cranking speed is over 150 rpm. Is cranking speed over 150 rpm?
a. Yes; Go to step 10.
6

All information subject to change without notice.

Copyright © 2016 DETROIT DIESEL CORPORATION

03 07-16

03 07-16
b. No; determine the cause of low crank speed.
10. Turn the ignition OFF.
11. Has the engine had any gear train, camshaft, or flywheel repairs made?
a. Yes; verify proper gear train timing and proper flywheel installation. Refer to section "Camshaft Timing
Verification".
b. No; Go to step 12.
12. Remove the CMP sensor and inspect for damage. Is there damage to the sensor?
a. Yes; inspect the tone wheel on the intake camshaft for damage. Check gear train for excessive lash or damage. If
damage is found, repair as necessary and replace the camshaft position sensor. Refer to section "Removal of the
Camshaft Position Sensor".
b. No; replace the camshaft position sensor. Refer to section "Removal of the Camshaft Position Sensor".

All information subject to change without notice.

03 07-16

Copyright © 2016 DETROIT DIESEL CORPORATION

7