DTC P0A94 (19-21 9-Speed A/T)
DTC P0A94 : DC-DC Converter Performance Problem
NOTE: Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems .
| DTC Description | Confirmed DTC | Pending DTC |
|---|---|---|
| P0A94 DC-DC Converter Performance Problem |
DTC (PGM-FI)
- DTC check
- 1. Turn the vehicle to the ON mode.
- 2. Clear the DTC with the HDS.
- 3. Turn the vehicle to the OFF (LOCK) mode.
- 4. Test-drive the vehicle under the auto idle stop system operating condition, and stop the engine using auto idle stop.
NOTE: If the auto idle stop system indicator (amber) blinks and the engine keeps running, go to step 1-5.
- 5. Check for Pending or Confirmed DTCs with the HDS.
DTC Description Confirmed DTC Pending DTC P16E5 LIN Communication Error (Powertrain Control Module (PCM)-DC-DC Converter) Is DTC P16E5 indicated?
YES
Go to the troubleshooting for DTC P16E5 - Refer to: DTC P16E5 (19-21 9-Speed A/T) .
NO
Go to step 2.
- Problem verification
- 1. Check for Pending or Confirmed DTCs with the HDS.
DTC Description Confirmed DTC Pending DTC P0A94 DC-DC Converter Performance Problem Is DTC P0A94 indicated?
YES
The failure is duplicated. Go to step 3.
NO
Check the fuses in the under-hood fuse/relay box and the auxiliary under-hood fuse/relay box. If the fuse (s) is blown, repair a short in the fuse circuit. If it is OK, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the DC-DC converter and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot - Refer to: How to Troubleshoot the Fuel and Emissions Systems .
- Determine possible failure area (CST line shorted, others)
- 1. Check the parameter (s) below with the HDS.
Signal Threshold Current conditions Values Unit Values Unit DC-DC CONVERTER CST ERROR Normal Do the current condition (s) match the threshold?
YES
Go to step 5.
NO
Go to step 4.
- Shorted wire check (CST line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Jump the SCS line with the HDS, and wait more than 1 minute.
- 3. Disconnect the following connectors.
DC-DC converter connector A (3P) PCM connector A (50P) - 4. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode DC-DC converter connector A (3P): disconnected PCM connector A (50P): disconnected Test point 1 DC-DC converter connector A (3P) (female terminals) No. 2: Test point 2 Body ground Is there continuity?
YES
Repair a short in the CST wire between the PCM (A9) and the DC-DC converter.
NO
The CST wire is OK. Replace the DC-DC converter . If DTC P0A94 was indicated after DC-DC converter replaced, check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T) , then recheck.
If DTC P0A94 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T) .
- Open wire check (GND line)
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the following connector.
DC-DC converter connector B (5P) - 3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode DC-DC converter connector B (5P): disconnected Test point 1 DC-DC converter connector B (5P) (female terminals) No. 4: Test point 2 Body ground Is there continuity?
YES
Go to step 6.
NO
Repair an open in the GND wire between the DC-DC converter and G301.
- Determine possible failure area (DC-DC converter input/output lines)
- 1. Reconnect DC-DC converter connector B (5P).
- 2. Turn the vehicle to the ON mode.
- 3. Check the parameter (s) below with the HDS.
Signal Current conditions Values Unit DC-DC CONVERTER INPUT ERROR 1 DC-DC CONVERTER INPUT ERROR 2 DC-DC CONVERTER OUTPUT ERROR 1 DC-DC CONVERTER OUTPUT ERROR 2 Do these parameters indicate Malfunction?
DC-DC converter input error 1 indicates Malfunction
Go to step 7.
DC-DC converter input error 2 indicates Malfunction
Go to step 9.
DC-DC converter output error 1 indicates Malfunction
Check for +B OUT1 circuit shorted, or aftermarket parts connected to +B OUT1 wire. Repair a short in +B OUT1 circuit or remove the aftermarket parts if needed. If +B OUT1 wire is OK, replace the DC-DC converter .
DC-DC converter output error 2 indicates Malfunction
Check for +B OUT2 circuit shorted, or aftermarket parts connected to +B OUT2 wire. Repair a short in +B OUT2 circuit or remove the aftermarket parts if needed. If +B OUT2 wire is OK, replace the DC-DC converter .
All parameters indicates Normal
DC-DC converter input and output lines are OK. Replace the DC-DC converter .
- Fuse check
- 1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Check the following fuse.
Fuse No. B14 - Refer to:
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021), or
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021)Is the fuse OK?
YES
Go to step 8.
NO
Check for a short in the +B DC/DC1 wire between the DC-DC converter and the No. B14 fuse, the +B OUT1 wire between the DC-DC converter, the under-hood fuse/relay box and the auxiliary under-dash fuse/relay box, and repair it if needed. Also replace the No. B14 fuse.
- Open wire check (+B DC/DC1 line)
- 1. Disconnect the following connector.
DC-DC converter connector B (5P) - 2. Measure the voltage between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode DC-DC converter connector B (5P): disconnected Test point 1 DC-DC converter connector B (5P) (female terminals) No. 1: Test point 2 Body ground Is there battery voltage?
YES
The +B DCDC1 IN1 wire is OK. Replace the DC-DC converter . If DTC P0A94 was indicated after DC-DC converter replaced, check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T) , then recheck. If DTC P0A94 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T) .
NO
Repair an open in the +B DC/DC1 wire between the DC-DC converter and the No. B14 fuse. - Refer to:
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021) or
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021)
- Fuse check
- 1. Check the following fuse.
Fuse No. B13 - Refer to:
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021), or
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021)Is the fuse OK?
YES
Go to step 10.
NO
Check for a short in the +B DC/DC2 wire between the DC-DC converter and the No. B13 fuse, the +B OUT2 wire between the DC-DC converter and the auxiliary under-dash fuse/relay box, and repair it if needed. If the wires are OK, replace the DC-DC converter . Also replace the No. B13 fuse.
- Open wire check (+B DC/DC2 line)
- 1. Disconnect the following connector.
DC-DC converter connector B (5P) - 2. Measure the voltage between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode DC-DC converter connector B (5P): disconnected Test point 1 DC-DC converter connector B (5P) (female terminals) No. 2: Test point 2 Body ground Is there battery voltage?
YES
The +B DC/DC2 wire is OK. Replace the DC-DC converter .
If DTC P0A94 was indicated after DC-DC converter replaced, Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T) , then recheck.
If DTC P0A94 goes away and the PCM was substituted, replace the original PCM - Refer to: PCM Removal and Installation (19-21 9-Speed A/T) .
NO
Repair an open in the +B DC/DC2 wire between the DC-DC converter and the No. B13 fuse. - Refer to:
Fuse to Components Index (Without Auto Idle Stop System) (2019 2020 2021) or
Fuse to Components Index (With Auto Idle Stop System) (2019 2020 2021)