What this code means
P16E3 may indicate a LIN communication problem involving the PCM and the battery-sensor side of the charging system.
What the vehicle may do
- The vehicle may show a warning light.
- Battery or charging-management behavior may be affected.
- The vehicle can also appear to operate normally.
Possible fault areas
- Possible loose terminals or poor connections at the battery sensor or PCM.
- Possible LIN circuit short or open.
- Possible battery sensor power-feed issue.
- Possible battery sensor, alternator-side, or PCM-side communication involvement.
Diagnostic path
Opening context
On this 2010 to 2016 Honda CR-V L4-2.4L, P16E3 is basically the PCM saying it may not be getting the LIN communication it expects from the 12 volt battery sensor side of the charging system. The vehicle may have a warning light, battery or charging-management symptoms, or it may feel completely normal. The possible areas are the battery sensor connections, the PCM side of the circuit, the LIN wire, and the sensor power feed. Start with the basic system checks, and do not skip a quick look for loose terminals at the 12 volt battery sensor and the PCM.
Verify the fault first
First, prove the fault is active. Turn the vehicle to the ON mode, clear the DTC with the HDS, wait for 10 seconds, and check for pending or confirmed codes again. If P16E3 comes right back, the failure is duplicated and you can move into circuit testing. If it does not come back, treat it as intermittent for now. Check the battery sensor and PCM terminals for poor fit or looseness, and if captured operating data is available, try to reproduce the same conditions instead of guessing.
Use the companion-code path as a divider
Next, check pending and confirmed codes with the HDS again. If the companion battery-sensor communication code is also present, stay on the LIN short-to-ground style path. If it is not present, skip ahead to the fuse and sensor power-feed checks.
If the companion code is present, check for a short on the LIN line
With the vehicle in OFF (LOCK) mode, disconnect the 12 volt battery sensor 2P connector. Check continuity from the 12 volt battery sensor 2P connector No. 2 to body ground. If there is continuity, continue isolating the short. Jump the SCS line with the HDS, wait more than 1 minute, and keep watching that continuity while disconnecting PCM connector B (51P), then the alternator 1P connector, one at a time. If the continuity goes away when one of those connectors is unplugged, the LIN wire itself is being cleared by that disconnect, so follow that result to the part identified by the test. If continuity never goes away, repair the short in the LIN(BATT SENSOR)/LIN wire between the 12 volt battery sensor, the alternator, and the PCM at B40.
If the LIN short check does not show continuity, separate the sensor from the circuit
If the first LIN-to-ground check has no continuity, turn the vehicle OFF (LOCK), reconnect the 12 volt battery sensor 2P connector, and disconnect the alternator 1P connector. Now check continuity from alternator 1P connector No. 1 to body ground. If there is continuity, replace the 12 volt battery sensor. If there is no continuity, jump the SCS line with the HDS, wait more than 1 minute, then disconnect the 12 volt battery sensor 2P connector and PCM connector B (51P). Check continuity between 12 volt battery sensor 2P connector No. 2 and PCM connector B (51P) No. 40. If continuity is good, the LIN wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM and recheck. If the code goes away after an update, that completes this path. If the code goes away with the known-good PCM installed, replace the original PCM. If there is no continuity in that wire check, repair the open in the LIN(BATT SENSOR)/LIN wire between the 12 volt battery sensor and PCM B40.
If the companion code is not present, check the fuse and power feed
When the companion code is not present, go to the power-feed side. Turn the vehicle OFF (LOCK), and check fuse No. A14 (10 A) in the under-hood fuse/relay box. If the fuse is not OK, repair the short in the +B HORN wire between the 12 volt battery sensor and the No. A14 (10 A) fuse, and replace the No. A14 (10 A) fuse. If the fuse is OK, disconnect the 12 volt battery sensor 2P connector, turn the vehicle ON, and measure voltage from 12 volt battery sensor 2P connector No. 1 to body ground. If there is no battery voltage, repair the open in the +B HORN wire between the 12 volt battery sensor and the No. A14 (10 A) fuse. If battery voltage is present, turn the vehicle OFF (LOCK), jump the SCS line with the HDS, wait more than 1 minute, disconnect PCM connector B (51P), and check continuity from 12 volt battery sensor 2P connector No. 2 to PCM connector B (51P) No. 40. If continuity is present, replace the 12 volt battery sensor. If continuity is not present, repair the open in the LIN(BATT SENSOR)/LIN wire between the 12 volt battery sensor and PCM B40.
Verification and takeaway
After the repair, keep verification separate from the testing path. Clear the code with the HDS, wait for 10 seconds, and confirm P16E3 does not return as pending or confirmed. The main takeaway is to let the code split the path: first prove the fault, then decide whether you are chasing a LIN short, a sensor-side issue, a power-feed problem, or an open LIN circuit. For more diagnostic training, visit stepdiagnostics.com.
Final check
P16E3 is often best approached by confirming the fault first, then separating LIN communication faults from sensor power-feed faults.
For more guided automotive diagnostics, visit STEP Diagnostics.
