DTC P1581 (19): Motor Power Inverter (MPI) Module Current Signal Circuit Low Input; DTC P1587 (19): Motor Power Inverter (MPI) Module Current Signal Circuit Low Input

NOTE:

Information marked with a asterisk (*) applies to 2005-2006 models.
Information marked with double asterisk (**) applies to 2000-2004 models.

Reset the MCM (see HOW TO RESET THE MCM ).
Turn the ignition switch ON (II).
Is DTC P1581 (19)** (P1587 (19)*) indicated?
1. YES - Go to step 3.
2. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the MPI module current sensor and at the MCM.
Turn the ignition switch OFF.
Turn the battery module switch OFF (see TURNING OFF POWER TO THE HIGH VOLTAGE CIRCUIT ).
Remove the IPU lid (see TURNING OFF POWER TO THE HIGH VOLTAGE CIRCUIT ).
Turn the ignition switch ON (II).
Measure voltage between MCM connector terminals B18 and B25.

Fig 1: Measuring Voltage Between MCM Connector Terminals B18 And B25
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there more than 0.2 V?
1. YES - Substitute a known-good MCM, and recheck. If the symptom/indication goes away, replace the original MCM.
2. NO - Go to step 8.
Measure voltage between MCM connector terminals B25 and C24.

Fig 2: Measuring Voltage Between MCM Connector Terminals B25 And C24
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?
1. YES - Go to step 9.
2. NO - Substitute a known-good MCM, and recheck. If the symptom/indication goes away, replace the original MCM.
Measure voltage between junction board 16 connector terminals No. 3 and No. 11.

Fig 3: Measuring Voltage Between Junction Board 16 Connector Terminals No. 3 And 11
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?
1. YES - Go to step 10.
2. NO - Repair open in the wire between the MCM (C24) and the junction board.
Measure voltage between junction board 16 connector terminals No. 9 and No. 11.

Fig 4: Measuring Voltage Between Junction Board 16 Connector Terminals No. 9 And 11
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 2.5 V?
1. YES - Repair open in the wire between the MCM (B18) and the junction board.
2. NO - Go to step 11.
Disconnect MCM connector B (25P).
Check for continuity between junction board 16P connector terminal No. 9 and body ground.

Fig 5: Checking Continuity Between Junction Board 16P Connector Terminal No. 9 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 13.
2. NO - Substitute a known-good MCM, and recheck. If the symptom/indication goes away, replace the original MCM.
Disconnect the junction board 16P connector.
Check for continuity between body ground and junction board 16P connector terminal No. 9.

Fig 6: Checking Continuity Between Body Ground And Junction Board 16P Connector Terminal No. 9
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair short to ground in the wire between the MCM (B18) and the junction board 16P connector.
2. NO - Replace the battery module (see BATTERY MODULE REMOVAL/INSTALLATION ).