AutoShift®/UltraShift Gen3
TRTS0930 EN-US
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July 2024 - A

Power-Up Sequence Test

Overview

This test does not relate to any specific fault code, but must be completed if the self check fails at power-up.

Detection

The TECU checks the program memory every time the key is turned on.

Fallback

This causes an In-Place fallback while moving and a self-check failure if it occurs during power-up.

Possible Causes

This fault code can be caused by any of the following:

  • Vehicle Harness
  • Shift Control Device
  • TECU

Component Identification

_Graphics/LineArt/trts0930s2p1b.png
  • Side view of pushbutton shift control
  • Transmission controller 30-way connector
  • Top view of pushbutton shift control
  • Eaton Cobra Lever

Power-Up Sequence Test

A
Purpose:Measure battery voltage. Visually inspect the batteries, inline fuse and power and ground supplies at the batteries.

  1. Key off.

  2. Remove and clean all battery and battery-to- frame connections.

  3. Remove and clean ground supply to engine ECU.

  4. Inspect starter/battery and inline 30-amp fuse holder connections for corrosion or damaged contacts.

  5. Measure voltage across batteries.

  • If voltage is 11 to 13 volts on a 12-volt system or 22 to 26 on a 24-volt system, proceed with battery load test. Repair or replace batteries as required. Go to Step B

  • If voltage is outside of range, repair or replace batteries and charging system as required. Repeat this step.

B
Purpose:Verify proper ground path between the batteries and the transmission harness 4-way diagnostic connector.

  1. Locate diagnostic port on Transmission Harness.

  2. Key on.

  3. Measure voltage between Pin C and the battery negative post.

  • If voltage is 0.70 volts or less, Go to Step C

  • If voltage is outside of range, repair battery ground supply to TECU. Repeat test.

C
Purpose:Measure proper battery voltage at the transmission harness 4-way diagnostic connector.

  1. Locate diagnostic port on Transmission Harness.

  2. Key on.

  3. Measure voltage between Pin B and Pin C.

    Warning
    Do not load test at the diagnostic port.

  • If voltage is within 0.6 volts of battery voltage, Go to Step D

  • If voltage is outside of range, repair battery power supply to TECU. Fuse may be blown. Repeat test.

D
Purpose:Measure proper ignition voltage at the transmission harness 4-way diagnostic connector.

  1. Key on.

  2. Measure voltage between Pin A and Pin C.

  • If voltage is within 0.6 volts of battery voltage, Go to Step E

  • If voltage is outside of range, repair Ignition power supply to ECU. Fuse may be blown. Repeat test.

E
Purpose:Visually identify if the vehicle is equipped with a shift lever or push button.

  1. Is vehicle equipped with an Shift Lever?

F
Purpose:Visually identify if the push button is an Eaton built push button or an OEM built J1939 push button.

  1. Is it an Eaton Push Button or OEM J1939 Shift Device?

  • If an Eaton Push Button Shift Control, Go to Step G

  • If an OEM J1939 Shift Device, refer to OEM for troubleshooting procedures.

G
Purpose:Visually observe the Service light during key-on power up.

  1. Key on.

  2. Observe Service light.

    Note: If Service light is flashing, go to Diagnostics Procedure.

H
Purpose:Measure the voltage supply at the Shift Control device.

  1. Key off.

  2. Disconnect Shift Control 30-way connector.

  3. Key on.

  4. Measure voltage between Pin C1 and Pin J3 on the Shift Control 30-way.

I
Purpose:Verify that a proper ground path is being supplied to the Shift Control Device through the Vehicle Harness and test for a short to ground.

  1. Key off.

  2. Disconnect negative battery cable.

  3. Disconnect 38-way Vehicle Harness from TECU.

  4. Measure resistance between TECU Pin 25 and Shift Control connector Pin J3 and from then from Pin J3 to ground.

  • If resistance from Pin 25 to J3 is 0 to 0.3 ohms and resistance from J3 to ground is OL / Open, Go to Step J

  • If resistance is outside of range, repair the Vehicle Harness. Go to Step V

J
Purpose:Measure the resistance of the ignition voltage supply wire to the Shift Control Device through the Vehicle Harness and test for a short to ground.

  1. Measure resistance between TECU Pin 31 and Shift Control connector Pin C1 and then from Pin C1 to ground.

  • If resistance from Pin 31 to C1 is 0 to 0.3 ohms and resistance from C1 to ground is 10K or OL, replace the TECU. Go to Step V

  • If resistance is outside of range, repair the Vehicle Harness. Go to Step V

K
Purpose:Visually identify if the shift lever is an Eaton built shift lever or an OEM built shift lever.

  1. Is vehicle equipped with an Eaton supplied Shift Lever or an OEM supplied Shift Lever.

L
Purpose:Visually observe the Service light during key-on power up.

  1. Key on.

  2. Observe Service light.

    Note: If Service light is flashing, See "Diagnostic Procedures"

  • If Service light illuminates for 1 second and turns off, test complete.

  • If Service light never comes on, Go to Step O

  • If Service light is on steady, Go to Step M

M
Purpose:Measure the voltage supply to the Service light during key-on power up.

  1. Disconnect Shift Lever 8-way connector.

  2. Key on.

  3. Measure voltage at Pin 6 and ground.

N
Purpose:- Test the Service light voltage supply for short to power through the Vehicle Harness.

  1. Key off.

  2. Disconnect negative cable.

  3. Disconnect 38-way Vehicle Harness connector.

  4. Measure resistance between Pin 6 and Pin 4.

O
Purpose:Measure the voltage supply to the Service light during key-on power up.

  1. Key off.

  2. Disconnect Shift Lever 8-way connector.

  3. Key on.

  4. Measure voltage between Pin 3 and Pin 6.

P
Purpose:Verify that a proper ground path is being supplied to the Shift Lever through the Vehicle Harness and test for a short to ground.

  1. Key off

  2. Disconnect 38-way Vehicle Harness connector on TECU.

  3. Measure resistance between Pin 3 on the 8-way connector and Pin 25 on the 38-way connector and from Pin 25 to ground.

    Note: On Peterbilt disconnect Gear Display,

  • If resistance between Pin 3 and Pin 25 is 0 to 0.3 ohms and resistance from Pin 25 to ground is OL, Go to Step Q

  • If resistance is outside of range, repair the Vehicle Harness between the Vehicle Harness 38-way connector Pin 25 and Vehicle Harness 8-way connector Pin 3. Go to Step V

Q
Purpose:Measure the resistance of the ignition voltage supply to the Shift Lever through the Vehicle Harness and test for a short to ground.

  1. Key off.

  2. Measure resistance between:

    • Vehicle Harness 38-way connector Pin 31 and Vehicle Harness 8-way connector Pin 4
    • Vehicle Harness 38-way connector Pin 31 and ground
R
Purpose:Measure the voltage supply to the Service light during key-on power up.

  1. Key off.

  2. Locate Service light connector on Vehicle Harness.

  3. Key on.

  4. Measure voltage across Pin A and Pin B on the Service light connector

  • If voltage is within 2 volts of battery voltage for 1 second, then 0 volts, test complete.

  • If no voltage is measured, Go to Step S

  • If voltage is within 2 volts of battery voltage continuously, Go to Step T

S
Purpose:Measure the resistance of the service light supply wire to the Shift Lever through the Vehicle Harness and test for a short to ground.

  1. Key off.

  2. Disconnect negative battery cable.

  3. Disconnect 38-way connector.

  4. Measure resistance from Pin A of the OEM connector to Pin 23 of the 38-way and from Pin 23 to ground.

T
Purpose:Test for a short to power at the Shift Lever Service light.

  1. Key off.

  2. Disconnect negative battery cable.

  3. Disconnect TECU 38-way connector.

  4. Measure voltage across Service light connector Pin A and Pin B.

V
Purpose:Verify that the system will properly power up.

  1. Key off.

  2. Reconnect all connectors and the negative battery cable.

  3. Key on.

  • If Power-Up Sequence Test completes, test complete.

  • If Power-Up Sequence Test fails Go to Step A find error in testing.