Power Circuits

Check for battery voltage between appropriate PCM connector Voltage Back-Up (VBU) terminal and ground. See POWER & GROUND CIRCUIT TERMINAL IDENTIFICATION . See Fig 1. If battery voltage does not exist, check appropriate PCM fuse. See PCM POWER CIRCUIT FUSE IDENTIFICATION . If fuse is okay, check for an open in wire between fuse and appropriate PCM connector terminal. See WIRING DIAGRAMS article.
Turn ignition on. Check for battery voltage between appropriate PCM connector Ignition Power (IGP) source terminal and ground. See POWER & GROUND CIRCUIT TERMINAL IDENTIFICATION . If battery voltage does not exist, check appropriate fuse. See PCM POWER CIRCUIT FUSE IDENTIFICATION . If fuse is okay, check for open in wire between fuse and appropriate PCM connector terminal. Check for defective ignition switch. See WIRING DIAGRAMS article.

POWER & GROUND CIRCUIT TERMINAL IDENTIFICATION

Application

⁽¹⁾ PCM Terminal

Ground Circuits

Logic Ground (LG1 & LG2)

A9, A22, D11 & D12

Power Ground (PG1 & PG2)

A10, A23, D11 & D12

Power Circuits

Ignition Switch In OFF Position (VBU) ⁽²⁾

C10

Ignition Switch In ON Position (IGP1 & IGP2) ⁽³⁾

A11 & A24

⁽¹⁾	Use illustration for terminal location. See Fig 1.

⁽²⁾	Voltage Back-up (VBU) power supply, battery voltage at all times.

⁽³⁾	Battery voltage with ignition on and zero volt with ignition off.

PCM POWER CIRCUIT FUSE IDENTIFICATION

Application

Fuse

Ignition In OFF Position

⁽¹⁾ No. 43 CLOCK RADIO (7.5-amps)

Ignition In ON Position

⁽²⁾ No. 4 ACG-S (15-amps)

⁽¹⁾	Located in underhood fuse/relay box.

⁽²⁾	Located in underdash fuse/relay box.

Fig 1: PCM Harness Connector Terminal Identification

Courtesy of AMERICAN HONDA MOTOR CO., INC.