SPN 5542 FMI 15 CT11, CT13, CT15 Low-Pressure Turbo Outlet Pressure Too High/TC1TOP Above Desired {7000} Caterpillar

SPN 5542 FMI 15 CT11, CT13, CT15 Low-Pressure Turbo Outlet Pressure Too High/TC1TOP Above Desired {7000}

Usage:

CT13 JFB

On Highway Truck:: CT660 (S/N: TGA1-UP; JFB1-UP; TJD1-UP; TEJ1-UP; TRK1-UP; TKL1-UP; TEM1-UP; TEP1-UP; TGR1-UP; TJS1-UP; TGS1-UP; TGT1-UP; TGW1-UP; TGD1-UP; TSW1-UP; TEY1-UP; TSY1-UP; TEZ1-UP; TGZ1-UP); CT680 (S/N: TWT1-UP; TKW1-UP; TRX1-UP; TRZ1-UP); CT681 (S/N: TWJ1-UP)

Introduction

This Special Instruction outlines the diagnostic procedure for Fault code SPN 5542 FMI 15 (Low-pressure turbo outlet pressure too high/TC1TOP above desired). Do not proceed to any diagnostic procedure with out first completely reading and understanding the outlines inside this Special Instruction.

Symptoms

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Table 1
Symptoms
DTC/Light	Description
SPN 5542 FMI 15	TC1TOP above desired
	Malfunction Indicator Light (MIL)

Possible Causes:

Restricted exhaust
Stuck or sticking closed EBPV
Failed ACV

Special Tools

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Table 2
Special Tools
Tool Description	Tool Number
Personal Computer (PC) with Engine Diagnostic Software	N/A
J1939 and J1708 RP1210B-Compliant Communication Device	N/A

Diagnostic Procedure

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Table 3
Step	Action	Decision
1	Check to see if the following faults are present in Electronic Control Module (ECM) (In addition to SPN 5542 FMI 15) : · Using PC with engine diagnostic software, check fault codes. · Look for SPN 5541,4452 (except FMI 15), and 5543. Are there any faults present?	Yes: Diagnose these faults before SPN 5542 FMI 15
1		No: Go to Step 2, Table 4

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Table 4
Step	Action	Decision
2	Check for SPN 3719 Diesel Particulate Filter (DPF) soot load fault codes present in ECM: · Using PC with engine diagnostic software, check fault codes. · Look for SPN 3719 FMI 0 or 16 ⁽¹⁾ Is SPN 3719 present?	Yes: Go to Symptom 2 of Troubleshooting, UENR5801, "CT11 and CT13 Non-SCR Aftertreatment System Diagnostics and Service Manual"
		No: Go to Step 3, Table 5

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^( 1 )

Excessive back pressure in the exhaust system, such as a plugged Diesel Oxidation Catalyst (DOC) and/or Diesel Particulate Filter (DPF) could set this fault.

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Illustration 1	g03725876
EBPV in Open Position (Key OFF) (1) Air Inlet (2) Valve Should Be Fully Open with No Air Pressure (3) Resting Against Stop

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Table 5
Step	Action	Decision
3	Inspect EBPV actuator: · Key OFF. · Inspect EBPV actuator and linkage. · Reference Illustration 1. Is the EBPV open (air cylinder NOT extended ) ?	Yes, Open: Go to Step 5, Table 7.
3		No, Closed or Partially Closed: Go to Step 4, Table 6

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Table 6
Step	Action	Decision
4	If EBPV actuator is closed or partially closed: · Key OFF. · Remove air inlet line from EBPV actuator cylinder. · Reference Illustration 1.	Yes: ACV has failed (air is being supplied to the EPBV with key OFF).
4	Does air escape as air inlet connection is removed?	No: EPBV is stuck or seized. Replace EBPV assembly

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Table 7
Step	Action	Decision
5	Check for physical damage and/or restriction to exhaust system: · Perform visual inspection of exhaust system. ⁽²⁾	Yes: Repair damage and/or restriction.
		No: Go to Step 6, Table 8
	Is the exhaust system damaged or restricted?

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^( 2 )

Excessive back pressure in the exhaust system, such as a plugged Diesel Oxidation Catalyst (DOC) and/or Diesel Particulate Filter (DPF) could set this fault.

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Table 8
Step	Action	Decision
6	Perform EBPV actuator operation test: · Ensure air tanks have at least 621 kPa (90 psi) of pressure. Key ON. · Using PC with engine diagnostic software, go to Tests-KOEO Tests-Actuator Test-Select Exhaust Back Pressure Valve. · Command EBPV to 5% through 95% duty cycle while watching air cylinder actuator movement (95% fully extends the air cylinder shaft and closes the valve) . ⁽³⁾ Refer to Illustration 1.	Yes: EBPV and ACV are working properly. An intermittent condition may exist or prior instructions were not followed.
		No: Go to Step 7, Table 9
	Does EBPV actuator move freely throughout its travel with no restrictions

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^( 3 )

Test will command actuator ON for 5 seconds and then return actuator to the Closed position.

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Table 9
Step	Action	Decision
7	Perform EBPV actuator operation test (air system) : · Remove air line from EBPC at the air cylinder connection. · Using PC with engine diagnostic software, go to Tests-KOEO Tests-Actuator Test-Select Exhaust Back Pressure Valve. · Command EBPV to 95%.	Yes: Check for failed air cylinder or stuck/seized EBPV. Replace if necessary.
7	Does air flow out of the disconnected air line?	No: Go to Step 8, Table 10.

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Table 10
Step	Action	Decision
8	Perform EBPV actuator operation test (air supply) : · Ensure air tanks have at least 621 kPa (90 psi) of pressure. · Loosen air supply line to ACV and verify if air escapes.	Yes: ACV has failed.
8	Does pressurized air escape?	No: Correct no air condition.

Parts Information

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Table 11
Part Number	Description	Qty	Ordering
3862539-B10	Engine harness connection - ACV pigtail kit	1	Cat dealer
4190970	ACV/Boost Control Solenoid Kit	1
3762709	EBPV/Brake Assembly, Exhaust	1