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Chevrolet P0AA4

17-NA-372 Service Procedure Refer toHigh Voltage Battery Disconnect Relay Replacement in SI. Parts Information Causal Part Description Part Number Qty x RELAY, HIGH VLTG BAT DISCON

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a Chevrolet/GM dealer or qualified EV service facility for diagnosis under bulletin 17-NA-372, especially if P0AA4 is current or returns.
Confidence95%

Quick answer

For a 2017 Chevrolet Bolt EV (US), DTC P0AA4 is addressed by GM bulletin 17-NA-372. If P0AA4 returns after the bulletin’s verification procedure, GM directs replacement of the High Voltage Battery Disconnect Unit (BDU).

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does P0AA4 mean?

For a 2017 Chevrolet Bolt EV (US), DTC P0AA4 is addressed by GM bulletin 17-NA-372. If P0AA4 returns after the bulletin’s verification procedure, GM directs replacement of the High Voltage Battery Disconnect Unit (BDU).

2. Technical explanation

The supplied official NHTSA-hosted GM communication states that technicians should monitor GDS 2 High Voltage Contactor Command Status (PID 430E) or listen for contactor opening/closing to verify state changes. After turning the vehicle back on and checking for DTCs, GM says to return the vehicle to the customer if no current DTCs are found. If DTC P0AA1 or P0AA4 returns, replace the High Voltage Battery Disconnect Unit (BDU). The bulletin refers technicians to the High Voltage Battery Disconnect Relay Replacement procedure in GM Service Information (SI).

3. What system is affected?

High Voltage Battery Disconnect Unit (BDU) / high-voltage battery disconnect relay.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

Not yet established by verified evidence.

6. Possible causes

  • GM bulletin 17-NA-372 identifies a returning P0AA4 as a condition for replacement of the High Voltage Battery Disconnect Unit (BDU). A more specific underlying cause is not yet established by verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Have the vehicle evaluated by a qualified Chevrolet/GM EV service technician.
  • Do not attempt high-voltage battery disconnect relay or BDU repair yourself.
  • Record whether P0AA4 is current or returns after diagnostic verification.

10. Step-by-step troubleshooting

  1. A qualified technician can verify contactor state changes using GDS 2 PID 430E, High Voltage Contactor Command Status, or by listening for contactor opening/closing, as described in bulletin 17-NA-372.
  2. After the vehicle is turned back on, check for DTCs.
  3. If there are no current DTCs, the bulletin says the vehicle may be returned to the customer.
  4. If P0AA4 returns, GM directs replacement of the High Voltage Battery Disconnect Unit (BDU).

11. When to contact service

Contact a Chevrolet/GM dealer or qualified EV service facility for diagnosis under bulletin 17-NA-372, especially if P0AA4 is current or returns.

12. What the service center may check

  • Verify high-voltage contactor state changes with GDS 2 PID 430E or by observing/listening for contactor operation, per GM bulletin 17-NA-372.
  • Turn the vehicle back on and check for current DTCs.
  • Determine whether P0AA4 returns.

13. Possible repair or resolution

  • If P0AA4 returns, replace the High Voltage Battery Disconnect Unit (BDU), according to GM bulletin 17-NA-372.
  • The bulletin lists relay part number 24284564, described as RELAY, HIGH VLTG BAT DISCONNECT, quantity 1.
  • Perform the repair using the High Voltage Battery Disconnect Relay Replacement procedure in GM Service Information (SI).

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM bulletin 17-NA-372, published November 21, 2017, is an official manufacturer communication hosted by NHTSA as MC-10139138-9999. It applies in the supplied evidence to the 2017 Chevrolet Bolt EV in the United States and addresses P0AA1 and P0AA4.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official source: NHTSA-hosted GM manufacturer communication, Bulletin 17-NA-372: https://static.nhtsa.gov/odi/tsbs/2017/MC-10139138-9999.pdf

19. Frequently asked questions

What does GM direct if P0AA4 returns?

GM bulletin 17-NA-372 directs replacement of the High Voltage Battery Disconnect Unit (BDU) if P0AA4 returns.

Which vehicle is supported by the supplied evidence?

The supplied applicability evidence supports the 2017 Chevrolet Bolt EV, US-market.

Can I continue driving or charging?

Not yet established by verified evidence.

Is this a recall?

Not yet established by verified evidence.

20. Sources & verification

ReferenceVerified
Chevrolet P0AA4: 17-NA-372 Service Procedure Refer toHigh Voltage… | EV Diagnostics