0510-16 SPN 2623 Service Bulletin/Repair Instructions

05 10-16
1
05 10-16
SUBJECT
DATE
SPN 2623 (CPC)(GHG17), SPN 2623 (CPC)(GHG14), and SPN

2623 (CPC)(EPA07;EPA10;GHG14)
May 2016
Additions, Revisions, or Updates

Publication Number / Title
Platform
Section Title
Change
DDC-SVC-MAN-0193
GHG17 DD

Medium Duty
SPN 2623/FMI 2, 8, 14 GHG17
New DD5 and DD8 diagnostic procedures
DDC-SVC-MAN-0191
DD Platform HDEP
SPN 2623/FMI 2, 8, 14 GHG17
Updated GHG17 HDEP diagnostic procedures
DDC-SVC-MAN-0084
DD Platform HDEP
SPN 2623/ FMI 2, 8 GHG14

SPN 2623/FMI 14 - EPA07EPA10-GHG14
Updated EPA07, EPA10 & GHG14 HDEP

diagnostic procedures
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.
05 10-16
Copyright © 2016 DETROIT DIESEL CORPORATION
3
2 SPN 2623/FMI 2 - GHG17
2
SPN 2623/FMI 2 - GHG17
Accelerator Pedal "In-Range" Fault

Table 1.

SPN 2623/FMI 2

Description
Pedal Position Sensors Deviation Too High
Monitored Parameter
GAS1, GAS2
Typical Enabling Conditions
Always On
Monitor Sequence
None
Execution Frequency
Continuous When Enabling Conditions Met
Typical Duration
Two Seconds
Dash Lamps
None
Engine Reaction
None
Verification
Key Cycle - Ignition ON
Figure 1. Analog Pedal Type
4
All information subject to change without notice.
Copyright © 2016 DETROIT DIESEL CORPORATION 05 10-16
05 10-16
Figure 2. Dual-Channel Analog Pedal

Table 2.

Williams Dual-Channel Pedal Connector and Pinout

Function
CPC Pinout
Connector Pinout
Comments
APS1
1/7
A
Sensor 1
GND1
1/4
B
APS 1 GND
VCC1 (+5V)
1/8
C
APS1 Power Supply
VCC2 (+5V)
3/3
D
APS2 Power Supply
GND2
3/2
E
APS2 GND
APS2
4/14
F
Sensor 2
Connector Body
Check as follows:

1. Turn the ignition ON (key ON, engine OFF).

2. Connect DiagnosticLink®; are any SPN 91/FMI 0, FMI 2, FMI 4, or FMI 8 fault codes active?

a. Yes; troubleshoot other faults first.

b. No; Go to step 3.

3. Check for proper configuration of the CPC against the server information. Does the CPC pedal type have the proper

configuration?

a. Yes; Go to step 4.

b. No; reprogram the CPC with the correct information as necessary. Verify repair.

4. Disconnect the AP.

5. Inspect the AP and harness side connectors for signs of damaged, bent, spread, corroded or unseated (pushed out) pins

and signs of moisture in the connector or wire damage near the connector. Is any damage found?

a. Yes; repair as necessary. Verify repair.

b. No; Go to step 6.

6. Measure the voltage between pin B of the AP harness connector and ground. Is voltage present?
All information subject to change without notice.
05 10-16
Copyright © 2016 DETROIT DIESEL CORPORATION
5
2 SPN 2623/FMI 2 - GHG17
7.
8.
9.
10.
11.
12.

13.

14.
15.

16.

17.
18.
a. Yes; repair a short to power between pin B of the AP harness connector and pin 4 of the CPC #1 connector.

Verify repair.

b. No; Go to step 7.

Measure the voltage between pin A of the AP harness connector and ground. Is voltage present?

a. Yes; repair a short to power between pin A of the AP harness connector and pin 7 of the CPC #1 connector.

Verify repair.

b. No; Go to step 8.

Is the vehicle equipped with a Williams Dual-Channel Analog Pedal?

a. Yes; Go to step 9.

b. No; Go to step 11.

Measure the voltage between pin F of the AP harness connector and ground. Is voltage present?

a. Yes; repair a short to power between pin F of the AP harness connector and pin 14 of the CPC #4 connector.

Verify repair.

b. No; Go to step 10.

Measure the voltage between pin E of the AP harness connector and ground. Is voltage present?

a. Yes; repair a short to power between pin E of the AP harness connector and pin 2 of the CPC #3 connector.

Verify repair.

b. No; Go to step 12.

Measure the voltage between pin F of the AP harness connector and ground. Is voltage present?

a. Yes; repair a short to power between pin F of the AP harness connector and pin 2 of the CPC #2 connector.

Verify repair.

b. No; Go to step 12.

Reconnect the AP.

Using DiagnosticLink, monitor PWM Pedal Signal GAS1 and PWM Pedal Signal GAS2 under the Instrumentation/

Chart tab.

Cycle Accelerator Pedal (AP) slowly several times with a full sweep from top to bottom of travel. Does voltage sweep

smoothly in relation to pedal travel? Do the percentages sweep smoothly in relation to pedal travel?

a. Yes; Go to step 15.

b. No; replace the AP. Refer to Original Equipment Manufacturer (OEM) literature.

Clear codes and cycle ignition OFF.

Turn the ignition ON (key ON, engine OFF).

Does the code return?

a. Yes; replace the AP, clear codes and verify repair. Refer to Original Equipment Manufacturer's (OEM)

literature.

b. No; Go to step 18.

Gently wiggle pedal and harness connector to simulate road vibration.
NOTICE: Do not tap on AP with metal object or tool as this may damage component.

NOTICE: A second technician may be required to monitor values during wiggle testing.

19. While performing wiggle test, monitor PWM Pedal Signal GAS1 and PWM Pedal Signal GAS2 under the

DiagnosticLink Instrumentation/Chart tab.

20. Cycle AP slowly several times with a full sweep from top to bottom of travel. Do the percentages sweep smoothly in

relation to pedal travel?

a. Yes; Go to step 21.

b. No; replace the AP, clear codes and verify repair. Refer to Original Equipment Manufacturer (OEM) literature.

21. Gently wiggle the Common Powertrain Controller (CPC) harness connectors to simulate road vibration.

22. While performing wiggle test, monitor PWM Pedal Signal GAS1 and PWM Pedal Signal GAS2 under the

DiagnosticLink Instrumentation/Chart tab.

23. Cycle AP slowly several times with a full sweep from top to bottom of travel. Do the percentages sweep smoothly in

relation to pedal travel?

a. Yes; Go to step 24.
6
All information subject to change without notice.
Copyright © 2016 DETROIT DIESEL CORPORATION 05 10-16
05 10-16
24.

25.

26.

27.
b. No; isolate that section of harness and inspect for wire chaffing, corrosion, improper connections or physical

damage and repair as necessary. Verify repair.

Disconnect the CPC #1 connector.

Disconnect the CPC #3 connector.

Disconnect the CPC #4 connector.

Inspect the CPC and the harness connectors for signs of damaged, bent, spread, corroded or unseated (pushed out) pins

and signs of moisture in the connector or wire damage near the connectors. Is any damage found?

a. Yes; repair as necessary. Verify repair.

b. No; replace the AP, clear codes and verify repair. Refer to Original Equipment Manufacturer (OEM) literature.

Verify repair.
All information subject to change without notice.
05 10-16
Copyright © 2016 DETROIT DIESEL CORPORATION
7
3 SPN 2623/FMI 8 - GHG17
3
SPN 2623/FMI 8 - GHG17
2-Channel Accelerator Pedal Signal 2 Missing

Table 3.

SPN 2623/FMI 8

Description
Channel 2 Sensor Signal Failed (High Or Low)
Monitored Parameter
GAS2
Typical Enabling Conditions
Always On
Monitor Sequence
None
Execution Frequency
Continuous When Enabling Conditions Met
Typical Duration
Two Seconds
Dash Lamps
CEL
Engine Reaction
None
Verification
Key Cycle - Ignition ON
Figure 3. Analog Pedal Type
8
All information subject to change without notice.
Copyright © 2016 DETROIT DIESEL CORPORATION 05 10-16
05 10-16
Figure 4. Dual-Channel Analog Pedal

Table 4.

Williams Dual-Channel Pedal Connector and Pinout

Function
CPC Pinout
Connector Pinout
Comments
APS1
1/7
A
Sensor 1
GND1
1/4
B
APS 1 GND
VCC1 (+5V)
1/8
C
APS1 Power Supply
VCC2 (+5V)
3/3
D
APS2 Power Supply
GND2
3/2
E
APS2 GND
APS2
4/14
F
Sensor 2
Connector Body
Check as follows:

1. Disconnect the Accelerator Pedal (AP).

2. Inspect the AP and harness side connectors for signs of damaged, bent, spread, corroded or unseated (pushed out) pins

and signs of moisture in the connector or wire damage near the connector. Is any damage found?

a. Yes; repair as necessary. Verify repair.

b. No; Go to step 3.

3. Turn the ignition ON (key ON, engine OFF).

4. Measure the voltage between pin B of the AP harness connector and ground. Is voltage present?

a. Yes; repair the short to power between pin B of the AP harness connector and pin 4 of the CPC #1 connector.

Verify repair.

b. No; Go to step 5.

5. Is the vehicle equipped with a Williams Dual-Channel Analog Pedal?

a. Yes; Go to step 6.

b. No; Go to step 12.

6. Measure the resistance between pin D of the AP harness connector and pin 3 of the CPC #3 connector. Is the

resistance less than five ohms?

All information subject to change without notice.
05 10-16
Copyright © 2016 DETROIT DIESEL CORPORATION
9
3 SPN 2623/FMI 8 - GHG17
7.
8.
9.
10.
11.
12.
13.
10
a. Yes; Go to step 7.

b. No; repair the open circuit between pin D of the AP harness connector and pin 3 of the CPC #3 connector.

Verify repair.

Measure the voltage between pin D of the AP harness connector and ground. Is voltage greater than 5.5 volts?

a. Yes; repair the short to battery power between pin D of the AP harness connector and pin 3 of the CPC #3

connector. Verify repair.

b. No; Go to step 8.

Measure the voltage between pin E of the AP harness connector and ground. Is voltage present?

a. Yes; repair the short to power between pin E of the AP harness connector and pin 2 of the CPC #3 connector.

Verify repair.

b. No; Go to step 9.

Measure the resistance between pin F of the AP harness connector and pin 14 of the CPC #4 connector. Is the

resistance less than five ohms?

a. Yes; Go to step 10.

b. No; repair the open circuit between pin F of the AP harness connector and pin 14 of the CPC #4 connector.

Verify repair.

Measure the resistance between pin F of the AP harness connector and ground. Is the resistance greater than 10K

ohms?

a. Yes; Go to step 11.

b. No; repair the short to ground circuit between pin F of the AP harness connector and pin 14 of the CPC #4

connector. Verify repair.

Measure the voltage between pin F of the AP harness connector and ground. Is voltage present?

a. Yes; repair the short to power between pin F of the AP harness connector and pin 14 of the CPC #4 connector.

Verify repair.

b. No; replace the AP. Refer to Original Equipment Manufacturer (OEM) literature.

Measure the resistance between pin F of the AP harness connector and pin 2 of the CPC #2 connector. Is the resistance

less than five ohms?

a. Yes; Go to step 13.

b. No; repair the open circuit between pin F and pin 2 of the CPC #2 connector. Verify repair.

Measure the voltage between pin F of the AP harness connector and ground. Is voltage present?

a. Yes; repair the short to power between pin F of the AP harness connector and pin 2 of the CPC #2 connector.

Verify repair.

b. No; replace the AP. Refer to Original Equipment Manufacturer (OEM) literature. Verify repair.
All information subject to change without notice.
Copyright © 2016 DETROIT DIESEL CORPORATION 05 10-16
05 10-16
4
SPN 2623/FMI 14 - GHG17
2-Channel Accelerator Pedal GAS1 and GAS2 Signal Missing

Table 5.

SPN 2623/FMI 14

Description
PWM Pedal Signal is Missing
Monitored Parameter
CAN Communication
Typical Enabling Conditions
Always Enabled
Monitor Sequence

12 3

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