02 21-16

1

02 21-16

SUBJECT

DATE

SPN 3936 (ACM)(GHG17)

February 2016

Additions, Revisions, or Updates
Publication Number / Title

Platform

Section Title

Change

DDC-SVC-MAN-0191

DD Platform
- GHG17

SPN 3936/FMI 18 GHG17

Procedure has been updated.

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.

02 21-16

Copyright © 2016 DETROIT DIESEL CORPORATION

3

2 SPN 3936/FMI 18 - GHG17

2

SPN 3936/FMI 18 - GHG17

Diesel Particulate Filter (DPF) Pressure - Out of Range Low
Table 1.
SPN 3936/FMI 18
Description

This Fault Code Sets when the Diesel Oxidation Catalyst (DOC) Inlet
Pressure Delta is Below Normal Operating Range for More Than 10
Seconds

Monitored Parameter

DOC Inlet Pressure Sensor

Typical Enabling Conditions

Always On

Monitor Sequence

None

Execution Frequency

Continuous When Enabling Conditions Met

Typical Duration

2 Seconds

Dash Lamps

MIL, CEL, SEL

Engine Reaction

Derate 25%

Verification

Run Engine Between 1200 to 1800 rpm With a Load Less Than 10%

Check as follows:
1. Visually inspect entire exhaust system for signs of leaks or damage. Are there any leaking or damaged exhaust
components?
a. Yes; repair as necessary.
b. No; Go to step 2.
2. Connect DiagnosticLink ®.
3. Using the Selective Catalytic Reduction (SCR) voltage service routine, monitor the Diesel Oxidation Catalyst (DOC)
inlet pressure (pin 87) and DPF outlet pressure (pin 72) voltages with the key ON, engine OFF.
4. Is the DOC inlet pressure sensor voltage between .44 to .56 volts?
a. Yes; Go to step 6.
b. No; Go to step 5.
5. Inspect electrical connector between DOC inlet pressure sensor connector and harness for bent, spread, or corroded
pins. Is there any damage found?
a. Yes; repair as necessary.
b. No; replace the DOC inlet pressure sensor.
Refer to section "Removal of the Diesel Oxidation Catalyst Inlet Pressure Sensor". Verify Repair.
6. Inspect the DOC pressure sensor tubes and elbows for leaks, kinks, or blockages. Were any leaks, kinks or blockages
found?
a. Yes; repair as necessary.
b. No; Go to step 7.
WARNING: ENGINE EXHAUST
To avoid injury from inhaling engine exhaust, always operate the engine in a well-ventilated area.
Engine exhaust is toxic.

WARNING: PERSONAL INJURY
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level
surface, parking brake is set, and the wheels are blocked.

4

All information subject to change without notice.

Copyright © 2016 DETROIT DIESEL CORPORATION 02 21-16

02 21-16

WARNING: HOT EXHAUST
During parked regeneration the exhaust gases will be extremely HOT and could cause a fire if
directed at combustible materials. The vehicle must be parked outside.
7. Perform a parked regeneration; during the regeneration, monitor (ASL: DOC Inlet Pressure).
8. During the parked regeneration, does either the DOC inlet pressure sensor drop to 0.0 psi at any time?
a. Yes; replace the failed sensor.
b. No; clear fault and release unit. The code likely occurred after extended idle and soot buildup has cleared.

All information subject to change without notice.

02 21-16

Copyright © 2016 DETROIT DIESEL CORPORATION

5