SWITCH AS-MAGNETIC 2543782 - Caterpillar

Generator Set: C15 GEN SET (S/N: C5E2774-2864; C5H1451-1580) C18 GEN SET (S/N: N1D174-275; EKW1023-1029) C9 GEN SET (S/N: C9E2024-2153)Introduction
Do not perform any procedure in this Special Instruction until you read this information and you understand this information.The above listed C9, C15, and C18 serial number generator sets may have been built with 12V rated relay which powers the Electronic Control Module (ECM). The applications that the12V rated relays are installed in require a 24V rated relay. The undersized relay will function normally but will eventually fail. Failure of the relay will cause the unit to shut down and fail to restart. The relay should be inspected for the affected generator sets. If the relay is rated for 12V, the relay should be removed and replaced with the 24V 206-9427 Relay .Safety Section
Do not disconnect equipment unless power has been disconnected or the area is known to be non-hazardous
Proper installation of electrical components is necessary to prevent component damage. To prevent electrical component damage, turn the engine start switch to the OFF position before connecting or disconnecting electrical components. Failure to follow this procedure may result in electrical component damage.
Relay Inspection and Replacement Instructions
Locate the Connection Box
Illustration 1 g02771278
(1) 166-0845 Connection Box The connection box (1) is located on the backside of the control box. Illustration 1 shows the general location of the connection box.Remove Connection Box Face Plate
Illustration 2 g02776777
(2) Four Phillips head bolts (3) Connection box face plate
Illustration 3 g02776779
(4) 24V 206-9427 Relay (5) Ground wire
The connection box face plate (3) is secured by four Phillips head bolts (2) shown in Illustration 2. Remove the four bolts with a standard Phillips head screwdriver.
Gently set the face plate down directly below the connection box since the grounding wire (5) is still connected to the face plate and the connection box. Refer to Illustration 3Inspect the Existing Relay
Illustration 4 g02776781
(6 ) Relay rating marking location
Illustration 5 g02776784
(7) 12V relay marking
Illustration 6 g02776787
(8) 24V relay markingInspect the existing relay to determine if the rating is for a 12V or 24V relay. Look for a "12VDC" or a "24VDC" marking. The markings (6) are found on the right side of the relay as installed in the connection box. Refer to Illustration 4 for an example of an installed relay with the markings. Illustration 5 shows the "12VDC" marking (7) and Illustration 6 shows the"24VDC" marking (8) on the relays.Replacing the 12V Relay
Illustration 7 g02776790
(9) Wires to be disconnected (10) Phillips head bolt
If the marking on the installed relay is "24VDC", the relay is correct and should be left as is. The connection box face plate should be replaced, and the four Phillips head bolts reinstalled and hand tightened.
If the marking on the installed relay is "12VDC", the relay is incorrect and must be removed. Remove the relay by unscrewing the Phillips head bolt (10) on the right side of the relay.
Once the bolt is removed, disconnect the wires (9) that are plugged into the terminals on the left side of the relay. Disconnect the wires, by