At J­46711­1, DPIM Overlay, measure
resistance to ground on 12V battery return
pins 18, 19, 20, and 21 of the DPIM 24­way
connector.

NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Was the resistance within specification?

5­572

Copyright © 2015 Allison Transmission, Inc. All Rights Reserved.

Section 5—DIAGNOSTIC CODES

DTC 73­41 (DPIM1) Inverter A Encoder Power Supply Out­of­Range Low (cont’d)
Step

Action

Value(s)

Yes

No

11

Leave the ignition OFF.
Disconnect the DPIM 24­way and
OEM 24­way connectors from the J­46711,
TCM/VCM/DPIM Breakout Harness.
3. Connect the OEM 24­way connector to the
DPIM 24­way connector.
4. Disconnect the red OEM 32­way connector
from the DPIM.
5. Connect the red DPIM 32­way connector
of the J­46711, TCM/VCM/DPIM Breakout
Harness, to the DPIM connector ONLY.
Leave the J­46711 disconnected from the
red OEM 32­way connector.
6. Turn ON the ignition.
7. At J­46711­1, DPIM Overlay, measure the
speed sensor supply Open Circuit Voltage
(OCV) at the red 32­way connector by
measuring the voltage between pin 6 and
pin 22 of the red 32­way DPIM connector.
8. At J­46711­1, DPIM Overlay, measure the
speed sensor supply Open Circuit Voltage
(OCV) at the red 32­way connector by
measuring the voltage between pin 9 and
pin 25 of the red 32­way DPIM connector.
Were both voltages within the specified range?

10­13V

Go to Step 12

Go to Step 19

12

1.
2.

Short in vehicle
harness. Repair
as necessary and
go to Step 20

Go to Step 13

1.
2.

3.

4.
5.

Turn OFF the ignition.
Disconnect the J­46711, TCM/VCM/
DPIM Breakout Harness, from the red
DPIM 32­way connector.
Connect the J­46711, TCM/VCM/
DPIM Breakout Harness, to the red
OEM 32­way connector ONLY.
Turn ON the ignition.
At J­46711­1, DPIM Overlay, measure for
voltage on pins 6, 7, 8, 9, 10, 22, 24, and
25.

NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Was voltage measured on any of the pins?

Copyright © 2015 Allison Transmission, Inc. All Rights Reserved.

5­573

Allison H 40/50 EP

DTC 73­41 (DPIM1) Inverter A Encoder Power Supply Out­of­Range Low (cont’d)
Step
13

Action
1.
2.
3.

4.

Value(s)

Yes

No

Short in vehicle
harness. Repair
as necessary and
go to Step 20

Go to Step 14

10­13V

Go to Step 15

Open or short in
vehicle harness.
Repair as
necessary and
go to Step 20

Less than 4
Ohms

Go to Step 16

Open or short in
vehicle harness.
Repair as
necessary and
go to Step 20

Turn OFF the ignition.
Disconnect the P1 and P2 encoder
connectors.
At J­46711­1, DPIM Overlay, measure for
shorts­to­ground on pins 6, 7, 9, 10, 22,
and 25.
At J­46711­1, DPIM Overlay, measure for
shorts to other wires on pins 6, 7, 8, 9, 10,
22, 24, and 25.

NOTE: There will be continuity between pins 8
and 24 of the red 32­way connector because
all motor speed sensor shield wires are spliced
together.
NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Were any shorts­to­ground or shorts to any
other wires found?
14

1.
2.

3.
4.
5.

Leave the ignition OFF.
Connect the J­46711, TCM/VCM/
DPIM Breakout Harness, to the red
DPIM 32­way connector. Leave it
connected to the red OEM 32­way
connector and leave the P1 and P2 encoder
connectors disconnected.
Turn ON the ignition.
Measure sensor supply voltage at the
P1 encoder connector on pin C.
Measure sensor supply voltage at the
P2 encoder connector on pin C.

NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Were both voltages within the specified range?
15

5­574

1.
2.

Turn OFF the ignition.
Leave the P1 and P2 encoder connectors
disconnected.
3. Use J­39197, Jumper Wire Kit, to measure
resistance to ground on pin B of the
P1 encoder connector.
4. Use J­39197, Jumper Wire Kit, to measure
resistance to ground on pin B of the
P2 encoder connector.
Were the measured resistance values within
specification?

Copyright © 2015 Allison Transmission, Inc. All Rights Reserved.

Section 5—DIAGNOSTIC CODES

DTC 73­41 (DPIM1) Inverter A Encoder Power Supply Out­of­Range Low (cont’d)
Step
16

Action
1.
2.
3.
4.
5.

6.

7.

Leave the ignition OFF.
Leave the P1 and P2 encoder connectors
disconnected.
Use J­39197, Jumper Wire Kit, to jumper
pins A and C on the P1 encoder connector.
Use J­39197, Jumper Wire Kit, to jumper
pins A and C on the P2 encoder connector.
Disconnect the red DPIM 32­way connector
from J­46711, TCM/VCM/DPIM Breakout
Harness, leaving J­46711 mated to the red
OEM 32­way connector.
At J­46711­1, DPIM Overlay, measure the
resistance between pins 6 and 10 of the
red OEM 32­way connector.
At J­46711­1, DPIM Overlay, measure the
resistance between pins 7 and 9 of the red
OEM 32­way connector.

Value(s)

Yes

No

Less than 4
Ohms

Go to Step 17

Open or short in
vehicle harness.
Repair as
necessary and
go to Step 20

Less than 4
Ohms

Go to Step 18

Open or short in
vehicle harness.
Repair as
necessary and
go to Step 20

NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Were the measured resistance values within
specification?
17

1.
2.
3.
4.
5.
6.

7.

8.

Leave the ignition OFF.
Leave the P1 and P2 encoder connectors
disconnected.
Remove the jumper wire from the P1 and
P2 encoder connectors.
Use J­39197, Jumper Wire Kit, to jumper
pins A and B on the P1 encoder connector.
Use J­39197, Jumper Wire Kit, to jumper
pins A and B on the P2 encoder connector.
Leave the J­46711, TCM/VCM/
DPIM Breakout Harness, mated to
the red OEM 32­way connector ONLY.
At J­46711­1, DPIM Overlay, measure the
resistance between pins 10 and 22 of the
red OEM 32­way connector.
At J­46711­1, DPIM Overlay, measure the
resistance between pins 7 and 25 of the red
OEM 32­way connector.

NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Were the measured resistance values within
specification?
18

Replace both the P1 and P2 speed sensors.
Have the speed sensors been replaced?

Go to Step 20

Copyright © 2015 Allison Transmission, Inc. All Rights Reserved.

5­575

Allison H 40/50 EP

DTC 73­41 (DPIM1) Inverter A Encoder Power Supply Out­of­Range Low (cont’d)
Step

Action

19

NOTE: In most cases, the Dual Power Inverter
Module (DPIM) is not at fault. Investigate
thoroughly before replacing the DPIM.

Value(s)

Yes

No

Go to Step 20

Replace DPIM. Contact Technical Assistance
Center (TAC) at 1­800­252­5283 for
DPIM replacement authorization. TAC will
require a snapshot.
Is the replacement of the DPIM complete?
20

5­576

In order to verify your repair:
1. Clear the DTC.
2. Operate the vehicle under normal driving
conditions.
Did the DTC return?

Begin the
diagnosis again.
Go to Step 1

Copyright © 2015 Allison Transmission, Inc. All Rights Reserved.

System OK

Section 5—DIAGNOSTIC CODES

DTC 73­41 (DPIM2) Inverter A Encoder Power Supply
Out­of­Range Low

Figure 5–52.
Overview:
The DPIM encoders are used to measure motor speed/direction and are required for motor operation.
DPIM2 uses separate power supplies for each of the encoders. This code is specific to the P1 sensor power
supply. The power supplied to this sensor is monitored to detect sensor/harness issues.
Action Taken When DTC Sets:
• MIL light illuminates
• Check System light illuminates
Possible Causes:
• 12V power supply issues (battery/charging)
• Short or open in 12V power supply wiring
• Internal DPIM fault
Tool Requirements:
• J­39700 Universal Breakout Box
• J­46711 TCM/VCM/DPIM Breakout Harness
• J­50165 DPIM2 Adapter Harness
• J­46708 Multimeter
• J­39197 Jumper Wire Kit
• Universal Allison DOC®
NOTE: DPIM2 has a blue Motor A Terminal Protection Assurance (TPA) key and breakout harness
J­46711 has a red Motor A TPA key. When servicing a DPIM2, use adapter harness J­50165 with
breakout box harness J­46711. This will convert the J­46711’s red connector TPA key to a blue
connector TPA key and allow it to connect to a DPIM2.

Copyright © 2015 Allison Transmission, Inc. All Rights Reserved.

5­577

Allison H 40/50 EP

DTC 73­41 (DPIM2) Inverter A Encoder Power Supply Out­of­Range Low (cont’d)
Step

Action

1

Are codes 13­12, 13­13 and/or 13­15 set along
with this code?

2

1. Install Universal Allison DOC®.
2. Start the engine.
3. Record the DTC snapshot.
4. Monitor TCM ignition voltage.
Is the voltage within the specified values?

3

Value(s)

Yes

No

Troubleshoot
these codes first.

Go to Step 2

Go to Step 3

Resolve voltage
problem. Go to
Step 20

Is code 73­41 active?

Go to Step 5

Go to Step 4

4

1.
2.

Clear the DTC.
Attempt to duplicate the conditions in the
failure record (mode, temperature, etc.).
Does code 73­41 return?

Go to Step 5

System OK

5

Perform a visual inspection of the blue 32­way
connector at the Dual Power Inverter Module
(DPIM) and at the P1 speed sensor.

Make repairs as
necessary and
go to Step 20

Go to Step 6

9­18V

NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Is there any water intrusion, damaged wiring,
etc. that may cause a loss and/or corruption of
signal?
6

1.
2.

7

At J­46711­1, DPIM Overlay, measure battery
supply voltage on pins 1, 2, 5, and 6 of the
DPIM 24­way connector.

Turn OFF the ignition.
Install J­39700, Universal Breakout
Box, to the DPIM 24­way and
OEM 24­way connectors using J­46711,
TCM/VCM/DPIM Breakout Harness.
3. Turn ON the ignition.
Is the harness connected and the ignition turned
back ON?

Go to Step 7

10.5­16V

Go to Step 8

NOTE: The vehicle OEM has responsibility
for all external wiring harness repair. Harness
repairs performed by Allison Transmission
distributors and dealers are not covered by
Allison Transmission warranty.
Is the voltage within the specified range?

5­578

Copyright © 2015 Allison Transmission, Inc. All Rights Reserved.

Open or short in
vehicle harness.
Repair as
necessary and
go to Step 20

Section 5—DIAGNOSTIC CODES

DTC 73­41 (DPIM2) Inverter A Encoder Power Supply Out­of­Range Low (cont’d)
Step

Action

Value(s)

Yes

No

8

At J­46711­1, DPIM Overlay, measure wakeup
signal voltage on pins 3 and 4 of the 24­way
connector.

9­16V

Go to Step 9

Open or short in
vehicle harness.
Repair as
necessary and
go to Step 20

9­16V

Go to Step 10

Open or short in
vehicle harness.
Repair as
necessary and