v Follow the suggested actions in the order in which they are listed in the Action column until the problemis solved.v See Chapter 3, “Parts listing, System x3400 Types 7973, 7974, 7975 and 7976,” on page 87 to determinewhich components are customer replaceable units (CRU) and which components are field replaceableunits (FRU).v If an action step is preceded by “(Trained service technician only),” that step must be performed only by atrained service technician.System-error log message ActionSystem shutoff due to +3.3V over voltage 1. Reseat the following components:a. Hot-swap power supplies (if any are installed)b. (Trained service technician only) Power-supply cables onthe system board2. (Trained service technician only) Replace the system board.System shutoff due to +3.3V under voltage 1. Reseat the following components:a. Hot-swap power supplies (if any are installed)b. (Trained service technician only) Power-supply cables onthe system board2. (Trained service technician only) Replace the system board.System shutoff due to 1.5V CPU over voltage 1. Reseat the following components:a. Hot-swap power supplies (if any are installed)b. (Trained service technician only) Power-supply cables onthe system board2. (Trained service technician only) Replace the system board.System shutoff due to 1.5V CPU under voltage 1. Reseat the following components:a. Hot-swap power supplies (if any are installed)b. (Trained service technician only) Power-supply cables onthe system board2. (Trained service technician only) Replace the system board.System shutoff due to board over temperature 1. Make sure that all fans have good airflow and are notobstructed.2. (Trained service technician only) Replace the system board.System shutoff due to continuous +5v overvoltage 1. Reseat the following components:a. Hot-swap power supplies (if any are installed)b. (Trained service technician only) Power-supply cables onthe system board2. (Trained service technician only) Replace the system board.System shutoff due to continuous +5v undervoltage 1. Reseat the following components:a. Hot-swap power supplies (if any are installed)b. (Trained service technician only) Power-supply cables onthe system board2. (Trained service technician only) Replace the system board.System shutoff due to CPU over temperature 1. Make sure that the heat sink has good airflow and is notobstructed.2. Reseat the following components:a. Heat sink cableb. (Trained service technician only) Heat sink80 System x3400 Types 7973, 7974, 7975, and 7976: Problem Determination and Service Guide
