IK1201120 ­ Interpreting AMS Snapshot

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IK1201120

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Major System: ENGINES
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Title : Interpreting AMS Snapshot
Applies To : 2010 + MaxxForce DT, 9, 10, N9 & N10 (ESN 3,300,000 and later) operating below 4,000' altitude

CHANGE LOG
12/4/2015 ­ Updated specification in step 6.
10/29/2015 - Added Change Log, and updated broken link.




DESCRIPTION
This article describes how to read and interpret the AMS (Air Management System) Test on 2010 and newer I-6 Engines.

Note: this article does not apply to units being operated at 4,000' or greater altitude.
Note: Units operating at an altitude greater than 4,000' may fail this test with a normally operating system.

SYMPTOM(s)
Diagnostic Trouble Code(s):
SPN

FMI

Description

27

0

EGRP fault: over temperature

27

3

EGRP signal Out of Range HIGH

27

4

EGRP signal Out of Range LOW

27

7

EGRP does not agree with commanded position

27

14

EGR System flow rate error during Air
Management Test

2659

10

EGR Slow Response Fault

2659

14

KOER AMT – EGR test failure

2659

20

EGR High Flow Rate detected

2659

21

EGR Low Flow Rate detected

2791

2

EGR valve communication fault

2791

3

EGRP signal Out of Range HIGH

2791

4

EGR voltage to LOW

2791

7

EGR valve unable to achieve commanded
position

2791

8

EGR valve not receiving ECM PWM signal

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IK1201120 ­ Interpreting AMS Snapshot

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EGR valve Initialization Fault

Customer Complaint(s):
Check engine light (related to one of the DTCs listed above)

SPECIAL TOOL(s) or SOFTWARE
Service Maxx

Testing Steps
1. Run Standard Test.
2. Run MAF Calibration Procedure.
3. Run and record the AMS test.
(Note: If any faults are active the EGR valve will not open during the AMS test causing the data to be unusable)
(Note: MAF Mean Value must be at least 1,100 mg during the first half of the test for the data to be usable, if below inspect for
intake restriction do not proceed until corrected)
4. Graph MAF Mean Value mg, IMP & EGR Position using Service Maxx.

Graph Analysis

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IK1201120 ­ Interpreting AMS Snapshot

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5. Calculate the EGR flow in mg by subtracting reading B from reading A then compare to specs:
Specs
A. 466 ST ≥ 690 mg
B. 466 HT ≥ 740 mg
C. 570 ≥ 850 mg
If the calculated EGR Flow Rate does not meet spec proceed with the following
A. Remove the ETV (Engine Throttle Valve) from the EGR mixer housing, using a flashlight and mirror inspect the inlet air heater for
severe plugging.
(80% or more plugging is required to cause an EGR flow issue)
B. If severe plugging is not present in the EGR mixer housing, cycle EGR valve 5 times with the output state test low / high and watch
plunger operation using a mirror and flashlight.
(Do not remove the EGR valve unless a SPN 27 and or SPN 2791 fault is set or valve fails to move)
C. If the EGR valve actuation does not log any DTCs, and unit still logs SPN 2659 FMI 14 remove rear EGR crossover pipe and inspect
for plugging (Replace if plugged and retest).

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IK1201120 ­ Interpreting AMS Snapshot

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6. Verify IMP meets spec during the first half of the test:
A. Spec is 2 PSI or greater

If IMP does not meet spec proceed with the following:
A. Below range: Follow IK1200648 Low Power Complaint due to Low Boost or ETV Boot Tear
B. Above range: Check turbocharger wastegate adjustment per IK1201103

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