Proper Assembly Sequences for Installing Air Inlet Heater Relay (12VDC Relay: 175-2301 Magnetic Switch, 24VDC Relay: 148-0757 Magnetic Switch){1090, 1408} Caterpillar

Agricultural Tractor:

MT735 MTS (S/N: AKN1-UP)

MT745 MTS (S/N: ALA1-UP)

MT755 (S/N: ALM1-UP)

MT765 MTS (S/N: AMS1-UP)

Industrial Engine:

3126B (S/N: BEJ1-UP; DCS1-UP)

C-9 (S/N: CLJ1-UP)

On-Highway Engines:

3126B (S/N: 8YL1-UP; 7AS1-UP; BES1-UP)

3126E (S/N: CKM1-UP; HEP1-UP; 9SZ1-UP)

Excavator:

322C L (S/N: BKJ1-UP)

325C L (S/N: CRB1-UP; BFE1-UP)

325C (S/N: BKH1-UP)

325C LN (S/N: CSJ1-UP)

325C L (S/N: BMM1-UP; BKT1-UP)

325C (S/N: BKW1-UP)

325C L (S/N: BLX1-UP)

330C L (S/N: CYA1-UP; HAA1-UP)

330C (S/N: JAB1-UP; GAG1-UP; BTM1-UP)

330C L (S/N: CAP1-UP; DKY1-UP)

330C LN (S/N: CGZ1-UP)

Integrated Toolcarrier:

IT28G (S/N: 8CR1-UP)

IT38G Series II CUSTOM (S/N: CSX1-UP)

IT38G (S/N: 7BS1-UP)

Motor Grader:

12H (S/N: AMZ1-UP)

Track-Type Loader:

953C (S/N: BBX1-UP)

Track-Type Tractor:

D5N PS LGP FTC (S/N: AKD1-UP)

D6R Series II DS LGP (S/N: BNC1-UP; ADE1-UP)

D6R Series II FTC (S/N: BLE1-UP)

D6R Series II DS XW (S/N: DAE1-UP)

D6R Series II STD FTC (S/N: BMJ1-UP; AGM1-UP)

D6R Series II DS XW (S/N: AEP1-UP)

D6R Series II DS STD (S/N: BLT1-UP)

D6R Series II DS XL (S/N: AAX1-UP; BMY1-UP)

D6R (S/N: DMP1-UP)

Wheel Loader:

928G (S/N: 6XR1-UP)

938G (S/N: 4YS1-UP; 6WS1-UP)

950G Series II (S/N: AYB1-UP; AYL1-UP; AXX1-UP)

962G Series II (S/N: BAB1-UP; BAD1-UP; AYE1-UP; AXY1-UP)

Introduction

The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.

Problem

Loose cables on the heater side or the Battery+ side of the Air Inlet Heater Relay may cause the Air Inlet Heater Relay to fail. Symptoms of a relay failure may include dead batteries or damage to the wiring harnesses.

Solution

When installing an Air Inlet Heater Relay, perform the following procedure to ensure proper cable retention. Be sure to use the hardware that is specified in the procedure and to follow the torque specifications that are listed. The changes that are listed in the following procedure are being implemented in production.

Before Assembly

1. Disconnect the power to the battery

2. Make sure that the wire assembly lugs are clean of corrosion and paint.
   Show/hide table

   Table 1

   Parts List
   Quantity	Part Number
   2	1H-3338 Lockwasher (Star Washer)
   2	012-0380 Lockwasher (Split Washer)
   2	5C-2890 Nut
   1	175-2301 Magnetic Switch
   1	148-0757 Magnetic Switch Gp
   Required Tools
   Quantity	Part Number
   1	4C-6936 Torque Wrench

Assembly on the Heater side of the Relay

1. Install a 1H-3338 Lockwasher (Star Washer) .

2. Install the heater cable.

3. Install a 012-0380 Lockwasher (Split Washer)

4. Install a 5C-2890 Nut . Use a 4C-6936 Torque Wrench to torque 5C-2890 Nut to 5.5 ± 0.5 N·m (49 ± 4 lb in).

Note: Make sure that the 5C-2890 Nut is torqued properly. Not enough torque or too much torque could cause some issues with the Air Inlet Heater Relay.

5. Reinstall the rubber boot on the heater side (if originally installed).

Assembly on the Orignal Equipment Manufacture (OEM) side of the Relay

1. Install a 1H-3338 Lockwasher (Star Washer) .

2. Install the wiring harness cable.

3. Install a 012-0380 Lockwasher (Split Washer)

4. Install a 5C-2890 Nut . Use a 4C-6936 Torque Wrench to torque the 5C-2890 Nut to 5.5 ± 0.5 N·m (49 ± 4 lb in).

Note: Make sure that the 5C-2890 Nut is torqued properly. Not enough torque or too much torque could cause some issues with the Air Inlet Heater Relay.

Illustration 1	g01484174
Assembly of cable with torque retention (1) 5C-2890 Nut (2) 012-0380 Lockwasher (3) Cable with terminal (4) 1H-3338 Lockwasher

Illustration 2	g01484193
Example of improper assembly (4) 1H-3338 Lockwasher (Star Washer) (5) Area of concern

Note: If the terminal on the cable is too thick as in Area (5) the nut may not fully engage on the terminal stud. The 1H-3338 Lockwasher (Star Washer) (4) may have to be removed in order for the nut to secure the cable properly.

Note: Make sure that a 4C-6936 Torque Wrench is used to torque the nuts.