Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC P16E2
DTC P16E2 : PGM-FI-ACG LIN Communication Error
NOTE:
- Before you troubleshoot, review the general troubleshooting information .
- Check for loose terminal on the alternator (+B terminal). If the alternator +B terminal was loose, DTC P16E2 will be stored.
| DTC Description | Confirmed DTC | Pending DTC | Freeze Frame |
|---|---|---|---|
| P16E2 PGM-FI-ACG LIN Communication Error |
DTC (PGM-FI)
- Problem verification
-1. Turn the vehicle to the ON mode.
-2. Clear the DTC with the HDS, and wait for 10 seconds.
-3. Check for Pending or Confirmed DTCs with the HDS.
DTC Description Confirmed DTC Pending DTC Freeze Frame P16E2 PGM-FI-ACG LIN Communication Error Is DTC P16E2 indicated?
YES
The failure is duplicated. Go to step 2.
NO
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the alternator and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot .
- DTC check
-1. Check for Pending or Confirmed DTCs with the HDS.
DTC Description Confirmed DTC Pending DTC Freeze Frame P16E3 PGM-FI-Battery Sensor LIN Communication Error Is DTC P16E3 indicated?
YES
Go to step 3.
NO
Go to step 7.
- Determine possible failure area (LIN line shorted, others)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Disconnect the following connector.
Alternator 1P connector -3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Alternator 1P connector: disconnected Test point 1 Alternator 1P connector No. 1 Test point 2 Body ground Is there continuity?
YES
Go to step 4.
NO
Go to step 5.
- Shorted wire check (LIN line)
-1. Jump the SCS line with the HDS.
Continue to check for continuity between alternator 1P connector terminal and body ground, while disconnecting these connectors, one at a time:
- 12 volt battery sensor 3P connector
- PCM connector B (51P)
Does continuity go away when one of the above connectors is disconnected?
YES
The LIN wire is OK. Replace the part that caused an open when it was disconnected.
NO
Repair a short in the LIN wire between the alternator, the 12 volt battery sensor, and the PCM.
- Determine possible failure area (LIN circuit shorted, others)
-1. Reconnect the alternator 1P connector.
-2. Disconnect the following connector.
12 volt battery sensor 3P connector -3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode 12 volt battery sensor 3P connector: disconnected Test point 1 12 volt battery sensor 3P connector No. 3 Test point 2 Body ground Is there continuity?
YES
NO
Go to step 6.
- Open wire check (LIN line)
-1. Jump the SCS line with the HDS.
-2. Disconnect the following connectors.
Alternator 1P connector PCM connector B (51P) -3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode 12 volt battery sensor 3P connector: disconnected Alternator 1P connector: disconnected PCM connector B (51P): disconnected Test point 2 PCM connector B (51P) No. 31 Test point 1 Alternator 1P connector No. 1 Is there continuity?
YES
The LIN wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P16E2 goes away and the PCM was updated, troubleshooting is complete. If DTC P16E2 goes away and the PCM was substituted, replace the original PCM .
NO
Repair an open in the LIN wire between the PCM (B31) and the alternator.
- Open wire check (LIN line)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Jump the SCS line with the HDS.
-3. Disconnect the following connectors.
Alternator 1P connector PCM connector B (51P) -4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Alternator 1P connector: disconnected PCM connector B (51P): disconnected Test point 1 PCM connector B (51P) No. 31 Test point 2 Alternator 1P connector No. 1 Is there continuity?
YES
The LIN wire is OK. Replace the alternator .
NO
Repair an open in the LIN wire between the PCM (B31) and the alternator.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.