NUMBER: 08 DDEC VI–16
S.M. REF.: listed in Table 1
ENGINE: DD15
DATE: April 2008
SUBJECT: SPN 1636 AND SPN 2630
PUBLICATION: DDC-SVC-MAN-0029
The procedure and direction for SPN 1636 have changed. SPN 1636 indicates a problem with the intake
manifold temperature circuit. SPN 2630 has been added. This code indicates a problem with the intake
air temperature circuit.
Section
Changes/Additions
SPN 1636/FMI 3, intake manifold temperature circuit failed high
SPN 1636, refer to section 90
SPN 1636/FMI 4, intake manifold temperature circuit failed low
SPN 2630/FMI 3, intake air temperature circuit failed high
SPN 2630, refer to section 94
SPN 2630/FMI 4, intake air temperature circuit failed low
Table 1
Manual Changes and Additions
SPN 1636
This SPN indicates the intake manifold temperature is outside of normal operating range.
SPN 1636/FMI 3
This diagnostic condition is typically intake manifold temperature circuit failed high.
Check as follows:
1. Check for multiple codes.
[a]
If 1636/3 and 2630/3 are present, go to step 6.
[b]
If only 1636/3 is present, go to the next step.
2. Disconnect the Intake Manifold Temperature Sensor.
3. Turn the ignition ON (key On, engine OFF).
4. Measure the voltage between pins 1 and 2 of the Intake Manifold Temperature Sensor harness
connector.
[a]
If the voltage is between 2.8 and 3 volts, replace the Intake Manifold Temperature Sensor.
Verify repairs.
[b]
If the voltage is less than 2.8 volts, go to the next step.
5. Measure the voltage between pin 2 of the Intake Manifold Temperature Sensor and ground.
[a]
If the voltage is between 2.8 and 3 volts, repair the wire between pin 1 of the Intake
Manifold Temperature Sensor connector and pin 52 of the MCM 120–pin connector.
Verify repairs.
[b]
If the voltage is less than 2.8 volts, repair the wire between pin 2 of the Intake Manifold
Temperature Sensor connector and pin 106 of the MCM 120–pin connector. Verify repairs.
6. Measure the voltage between pins 1 and 2 of the Intake Manifold Temperature Sensor harness
connector.
[a]
If the voltage is greater than 3 volts, repair the short to power on either pin 106 or 119 of
the MCM 120–pin connector. Verify repairs.
[b]
If no voltage is present, repair the open between pin 52 of the MCM 120–pin connector
and the Intake Manifold Temperature Sensor and the Intake Air Temperature Sensor.
Verify repairs.
SPN 1636/FMI 4
This diagnostic condition is typically intake manifold temperature circuit failed low.
Repair the short to ground between pin 2 of the Intake Manifold Temperature Sensor harness connector
and pin 106 of the MCM 120–pin connector. Verify repairs.
SPN 2630
This SPN indicates the intake air temperature is outside of normal operating range.
SPN 2630/FMI 3
This diagnostic condition is typically intake air temperature circuit failed high.
Check as follows:
1. Check for multiple codes.
[a]
If codes 1636/3 and 2630/3 are active at the same time, go to step 6.
[b]
If only fault 2630/3 is active, go to the next step.
2. Disconnect the Intake Air Temperature Sensor.
3. Turn the ignition ON (key On, engine OFF).
4. Measure the voltage between pins 1 and 2 of the Intake Air Temperature Sensor harness
connector.
[a]
If the voltage is between 2.8 and 3 volts, replace the Intake Air Temperature Sensor.
Verify repairs.
[b]
If the voltage is less than 2.8 volts, go to the next step.
5. Measure the voltage between pin 2 of the Intake Air Temperature Sensor harness and ground.
[a]
If the voltage is between 2.8 and 3 volts, repair the wire between pin 1 of the Intake Air
Temperature Sensor connector and pin 52 of the MCM 120–pin connector. Verify repairs.
[b]
If the voltage is less than 2.8 volts, repair the wire between pin 2 of the Intake Air
Temperature Sensor connector and pin 119 of the MCM 120–pin connector. Verify repairs.
6. Measure the voltage between pins 1 and 2 of the Intake Air Temperature Sensor harness
connector.
[a]
If voltage is greater than 3 volts, repair the short to power on either pin 106 or 119 of the
MCM 120–pin connector. Verify repairs.
[b]
If the no voltage is present, repair the open between pin 52 of the MCM 120–pin connector
and the Intake Air Temperature Sensor and Intake Manifold Temperature Sensor. Verify
repairs.
SPN 2630/FMI 4
This diagnostic condition is typically intake air temperature circuit failed low.
Repair the short to ground between pin 2 of the Intake Air Temperature Sensor harness connector and
pin 119 of the MCM 120–pin connector. Verify Repairs.
ADDITIONAL SERVICE INFORMATION
Additional service information is available in one of the DDEC VI troubleshooting guides.
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