Solution K03785558
Monday, November 4, 2019 5:44:00 PM CET

** SOLUTION **
Title

Vehicles With An Automated Manual Transmission Model F (AMT-F) With Crawler
Gearbox - Diagnostic Trouble Code (DTC) P10C7-97 Crawler Gear Engagement
System Blocked Shift To Neutral Position; Vehicle Stuck In Limp Mode Or Will Not
Shift Into Gear

Mack Models
Mack Model

MRU - TerraPro , TE - TerraPro , AN - Anthem , CHU - Pinnacle, Axle back , CXU Pinnacle, Axle front , GR - Granite , GU - Granite , PI - Pinnacle

Volvo Models
Volvo Model

VN , VNL , VNR , VNX , VAH , VHD

Emission Standard
Emission Standard

US17+OBD16 , US17+OBD18 , US17+OBD19

Engine family
Engine family

11L Engine , 13L Engine , MP7 , MP8

Transmission
Transmission

AMT-F With Crawler Gears , AMT-F With Crawler Gears

** SOLUTION **
Cause

Chassis equipped with an AMT-F may log DTC P10C7-97, accompanied by the vehicle
going into limp mode or possibly not being able to engage a gear. These symptoms may
be intermittent.
The crawler gear is engaged by moving the shifter to a forward position in the
gearbox. The shifter has an angled ramp cut on it that presses a plunger on the EVU
(Extension Valve Unit) to indicate that the unit has been engaged. If this plunger sticks
and does not move to the extended position indicating the crawler shifter actually moved
to the Neutral position the unit will think the shifter is still engaged and it was unable to
shift to neutral.

Solution

Guided Diagnostics are under review for this fault. Until improvements are made
to GD, please use this CBR to diagnose this fault.
Crawler function:
The crawler shifter cannot be engaged if the splitter shifter is in a gear. The splitter shifter
MUST be in neutral for the crawler shifter to move. Likewise, the splitter cannot move from
the neutral position if the crawler is in gear. The lockout function is mechanical and internal to
the gearbox.

• Before claiming a stuck crawler shift assembly ensure the splitter is in Neutral.

If the fault is inactive with high counts.
1. In Premium Tech Tool (PTT), run Test 4320-08-03-40 Gears or 4320-08-03-49 Ultra-low
Crawler Cylinder several times, or shift the transmission into and out of crawler gear with the
shift lever several times.
- See if the unit will log P10C7 and stop shifting.
- Listen for air leaks during the tests/shifting.
1.1 If the unit stops shifting and logs a fault: Go to the Active Fault section below.
1.2 If the vehicle will not log the fault:
1.1.1. Remove the EVU from the upper right side of the extension section.
1.1.2. Manually manipulate the plunger.
The return spring is very stiff but the plunger should feel smooth and not hang up in its
travel or feel like it is dragging in the bore.
1.1.3. If the plunger feels like it is dragging, replace the EVU.

If the fault is Active or becomes active during the above listed steps:
1. Carefully remove the EVU from the upper right side of the extension section.
2. Check that the position sensor plunger is not stuck.
2.1. If the plunger is found to be sticking: Replace the EVU.
2.2. If the plunger is not stuck and moves smoothly: Check the crawler shifter for
freedom of movement.
2.2.1. If the crawler is engaged, the shifter will be in the forward position (closer to the
engine).
2.2.1.1. Insert a pry bar in front of the shifter and pry the shifter rearward. It should
move freely except for the detent plunger pressure that is internal to the gearbox.
2.2.1.2. If the crawler shifter moves easily manually: Use a rubber tipped air blower to
put air to the two ports inside the gearbox to shift the unit with air pressure.

Solution visibility

Dealer distribution

Function(s)/component(s) affected
Function affected

engagement , Transmission Components

Function Group
Function Group

43 gearbox

Customer effect
Main customer effect

diagnostics/methodology , efficiency/abnormal behavior

Noise

hissing noise , blowing noise

Fault Codes And Error Codes
OBDII Diagnostic Trouble
Codes (P, U, B Format)

P10C7-97

Conditions
Vehicle operating mode
Frequency of occurrence of
problem
Location of problem

Administration

Shifting , during disengagement , during engagement
random
underneath cab

Author

UT9268H

Dealer ID

UT9268H

Last modified by

RU4469V

Creation date

27-09-2019 19:09

Date of last update

22-10-2019 21:10

Review date

31-12-2019 00:12

Status

Published

NA_Reviewer

UT9268H

NA_Author_Group

GTT

Variantes Kola
5XX - PTO
TRANSMISSION
MOUNTED ADM.
RWX - TRANSMISSION

PTOTRA-S - SINGLE PTO TRANSMISSION , PTOTRA-D - DOUBLE PTO
TRANSMISSION
F SERIES - AT2612F - VPT AUTOMATED TRANSMISSION 2600NM 12SPEED , F
SERIES - ATO2612F - VPT AUTOMATED TRANSMISSION 2600NM OVERDRIVE

RTX - AUTOMATIC
GEARBOX

TRA-AMT

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