GLASS 3822249 - Caterpillar

Introduction
This Special Instruction provides information in order to determine the correct replacement battery in an Electronic Control Module (ECM) for the machines that are listed. You should ensure that the product will not be damaged or the product will not be made unsafe by the operation, maintenance, or the repair procedures that are used.Procedure
Illustration 1 g02056313
Locate the serial number (2) on the ECM.The serial number is located beneath the part number (1) on the top face of the ECM.
Illustration 2 g02056314
Identify the fifth character (3) in the serial number.Note the fifth character in the serial number. This will be either a "B" or a "0". Refer to Illustration 2.
Determine the correct battery to order per Table 1.
Table 1
Fifth Character of ECM Serial Number    Part Number of Replacement Battery    
B     143-8480    
0     351-3551    
Illustration 3 g02056339
Replace the battery.Character "B" - The red (+V) wire is on pin 2 (4) .Character "0" - The red (+V) wire is on pin 1 (5) .ReferenceRefer to Troubleshooting Testing and Adjusting, RENR2631 for instruction on replacing the battery in the ECM.