DTC 42-1x ("x" can be 0 thru 9 or A thru F): No Signal From the Right Front Impact Sensor

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.

Special Tools Required

SRS Inflator Simulator 07SAZ-TB4011A
SRS Simulator Lead L 070AZ-SNAA300

NOTE:

Before doing this troubleshooting procedure, review SRS Precautions and Procedures (see PRECAUTIONS AND PROCEDURES ), General Troubleshooting Information (see DTC (DIAGNOSTIC TROUBLE CODES) ).
Before doing this troubleshooting procedure, review SRS Precautions and Procedures (see PRECAUTIONS AND PROCEDURES ), General Troubleshooting Information (see GENERAL TROUBLESHOOTING INFORMATION ), and 12 Volt Battery Terminal Disconnection and Reconnection (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ).
Before replacing the SRS unit, check the SRS unit software version with the HDS. If the software version is not the latest, update the SRS unit software (see SRS UNIT UPDATE ) and retest.

Clear the DTC memory (see HOW TO CLEAR DTCS ).
Turn the ignition switch to ON (II), then wait for 10 seconds.
Read the DTC (see HOW TO RETRIEVE DTCS ).
Is DTC 42-1x indicated?

YES -Go to step 4.

NO -Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures (see TROUBLESHOOTING INTERMITTENT FAILURES ). If another DTC is indicated, troubleshoot the DTC.
Turn the ignition switch to LOCK (0).
Do the 12 volt battery terminal disconnection procedure (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ), then wait at least 3 minutes.
Check the connections between SRS unit connector A (39P) and the SRS unit, between the right engine compartment wire harness 2P connector and the right front impact sensor (see FRONT IMPACT SENSOR REPLACEMENT ), and at right engine compartment wire harness 4P connector.
Are the connections OK?

YES -Go to step 7.

NO -Repair the poor connections and retest.
Disconnect SRS unit connector A (39P) from the SRS unit (see step 10 ).
Disconnect the right engine compartment wire harness 2P connector (A) from the right front impact sensor (B) (see FRONT IMPACT SENSOR REPLACEMENT ).

Fig 1: Identifying Right Engine Compartment Wire Harness 2P Connector And Right Front Impact Sensor
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure the resistance between SRS unit connector A (39P) terminals No. 38 and No. 39. There should be an open circuit or at least 1 MΩ.

Fig 2: Measuring Resistance Between SRS Unit Connector A (39P) Terminals No. 38 And No. 39
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Go to step 10.

NO -Short to another wire in the right engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.
Measure the resistance between body ground and SRS unit connector A (39P) terminals No. 38 and No. 39, individually. There should be an open circuit or at least 1 MΩ.

Fig 3: Measuring Resistance Between Body Ground And SRS Unit Connector A (39P) Terminals No. 38 And No. 39
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Go to step 11.

NO -Short to ground in the dashboard wire harness or the right engine compartment wire harness; replace the faulty harness, then clear the DTC.
Do the 12 volt battery terminal reconnection procedure (see 12 VOLT BATTERY TERMINAL DISCONNECTION AND RECONNECTION ).
Turn the ignition switch to ON (II), then wait for 10 seconds.
Measure the voltage between body ground and SRS unit connector A (39P) terminals No. 38 and No. 39, individually. There should be less than 0.2 V.

Fig 4: Measuring Voltage Between Body Ground And SRS Unit Connector A (39P) Terminals No. 38 And No. 39
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the voltage as specified?

YES -Go to step 14.

NO -Short to power in the right engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.
Turn the ignition switch to LOCK (0).
Connect the SRS inflator simulator (jumper connector) and the black lead (A) of simulator lead L to the right engine compartment wire harness 2P connector (B).

Fig 5: Connecting SRS Inflator Simulator And Black Lead Of Simulator Lead L To Right Engine Compartment Wire Harness 2P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure the resistance between SRS unit connector A (39P) terminals No. 38 and No. 39. There should be less than 1.0 Ω.

Fig 6: Measuring Resistance Between SRS Unit Connector A (39P) Terminals No. 38 And No. 39
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is the resistance as specified?

YES -Faulty right front impact sensor; replace the right front impact sensor (see FRONT IMPACT SENSOR REPLACEMENT ). If the problem is still present, replace the SRS unit (see SRS UNIT REPLACEMENT ).

NO -Open in the right engine compartment wire harness or the dashboard wire harness; replace the faulty harness, then clear the DTC.