K71 Transmission Control Module (MRG)

2025 Chevrolet Trailblazer ACTIV, FWDSECTION K71 Transmission Control Module (MRG)
GM3621452Courtesy of GENERAL MOTORS COMPANY
Connector Part Information
  • Harness Type: Engine Wiring Harness
  • OEM Connector: 34822-0453
  • Service Connector: 19329822
  • Description: 66-Way F 0.64, 2.8 Series, Sealed (BK with BK Terminal Position Assurance)
Terminal Part Information

Terminal Type ID Terminated Lead Diagnostic Test Probe Terminal Removal Tool
I 13587518 J-35616-35 (VT) J-38125-11A
II 19351723 J-35616-64B (L-BU) J-38125-213
Pin Size Color Circuit Function Terminal Type ID Option
1 - 5 - - - Not Occupied - -
6 0.5 VT / GY 139 Run/Crank Ignition 1 Voltage II MRG
7 0.5
0.5
VT / YE
VT / YE
5985
5985
Accessory Wake-Up Serial Data
Accessory Wake-Up Serial Data
II
II
LBP+MRG
MRG+L3T
8 0.5 GN / YE 6353 Input Speed Signal II MRG
9 0.5 GY / BU 6358 Output Speed Signal II MRG
10 - 12 - - - Not Occupied - -
13 0.5 BN / WH 585 Transmission Fluid Temperature Sensor Signal II MRG
14 0.5 YE / GN 4170 Transmission Output Shaft Speed Sensor Circuit 9V Reference II MRG
15 0.5 YE / BU 7763 Primary Pulley Pressure Sensor Signal II MRG
16 0.5 BU / RD 4162 Transmission Fluid Pressure Sensor 1 Circuit 5V Reference II MRG
17 - 22 - - - Not Occupied - -
23 0.5 YE / BU 4171 Transmission Input Shaft Speed Sensor Circuit 9V Reference II MRG
24 0.5 GN / VT 4510 Transmission Intermediate Speed Signal II MRG
25 0.5 BU / WH 3338 Transmission Internal Mode Switch Mode Control X II MRG
26 0.5 BK / BN 586 Transmission Fluid Temperature Sensor Low Reference II MRG
27 - - - Not Occupied - -
28 0.5 GY / BU 4324 Transmission Auxiliary Fluid Pump Feedback Signal II MRG
29 - 30 - - - Not Occupied - -
31 0.5 VT / GY 7764 Secondary Pulley Pressure Sensor Signal II MRG
32 - - - Not Occupied - -
33 0.5 GN / GY 6387 Transmission High Side Driver 1 Control II MRG
34 0.5 BU 2500 High Speed GMLAN Serial Data [+] 1 II MRG
35 0.5
0.5
BU
BU
2500
2500
High Speed GMLAN Serial Data [+] 1
High Speed GMLAN Serial Data [+] 1
II
II
LBP+MRG
MRG+L3T
36 0.5
0.5
WH
WH
2501
2501
High Speed GMLAN Serial Data [-] 1
High Speed GMLAN Serial Data [-] 1
II
II
LBP+MRG
MRG+L3T
37 0.5 WH 2501 High Speed GMLAN Serial Data [-] 1 II MRG
38 - - - Not Occupied - -
39 0.5
0.5
BU / BK
BU / BK
7493
7493
High Speed GMLAN Serial Data [+] 3
High Speed GMLAN Serial Data [+] 3
II
II
LBP+MRG
MRG+L3T
40 0.5
0.5
WH
WH
7494
7494
High Speed GMLAN Serial Data [-] 3
High Speed GMLAN Serial Data [-] 3
II
II
LBP+MRG
MRG+L3T
41 0.5 BK / BU 4165 Transmission Fluid Pressure Sensor 1 Circuit Low Reference II MRG
42 0.5 WH 7494 High Speed GMLAN Serial Data [-] 3 II MRG
43 0.5 BU / BK 7493 High Speed GMLAN Serial Data [+] 3 II MRG
44 0.5 GY / GN 6403 Clutch Solenoid Valve D Control II MRG
45 - 49 - - - Not Occupied - -
50 0.5 GY / BN 6388 Transmission High Side Driver 2 Control II MRG
51 - 52 - - - Not Occupied - -
53 0.5 GN / WH 2968 Transmission Auxiliary Fluid Pump Control II MRG
54 0.5 VT / WH 422 Torque Converter Clutch Solenoid Valve Control II MRG
55 - - - Not Occupied - -
56 0.5 GN / WH 1530 Transmission Line Pressure Control Solenoid Valve Control II MRG
57 0.5 BN 6400 Clutch Solenoid Valve A Control II MRG
58 0.5 YE / BN 6404 Clutch Solenoid Valve E Control II MRG
59 0.5 VT 4509 Transmission Clutch F Control II MRG
60 - 64 - - - Not Occupied - -
65 1.5
1.5
BK / WH
BK / WH
251
251
Signal Ground
Signal Ground
I
I
LBP+MRG
MRG+L3T
66 1.5 RD / YE 240 Battery Positive Voltage I MRG
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.