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Karma P0037

HO2S Heater Control Circuit Low Bank 1 Sensor 2

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService is recommended for inspection and correction under Karma bulletin TB-18-12-05. The supplied evidence does not establish urgency, drivability limits, or charging limits.
Confidence95%

Quick answer

For a 2018 Karma Revero in the US/North American market, P0037 means “HO2S Heater Control Circuit Low Bank 1 Sensor 2.” Karma bulletin TB-18-12-05 directs inspection of the secondary oxygen-sensor wiring routing, clip attachment, and connector for water ingress; the sensor may be replaced as needed.

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 P0037 mean?

For a 2018 Karma Revero in the US/North American market, P0037 means “HO2S Heater Control Circuit Low Bank 1 Sensor 2.” Karma bulletin TB-18-12-05 directs inspection of the secondary oxygen-sensor wiring routing, clip attachment, and connector for water ingress; the sensor may be replaced as needed.

2. Technical explanation

Verified evidence identifies P0037 as a low heater-control-circuit condition for Heated Oxygen Sensor (HO2S) Bank 1 Sensor 2. For the applicable vehicle population, the official Karma bulletin associates this code with inspection of the secondary O2 sensor and its wiring/connector condition.

3. What system is affected?

Secondary oxygen sensor (Bank 1 Sensor 2), including its heater-control circuit, wiring routing, retaining clips, and connector.

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

  • Improper routing of the secondary oxygen-sensor wiring.
  • Improper clip attachment for the secondary oxygen-sensor wiring.
  • Water ingress at the secondary oxygen-sensor connector.
  • The bulletin states that sensor replacement may be needed; it does not establish the specific internal sensor failure mode.

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

  • Arrange inspection by a qualified Karma service provider or qualified technician.
  • Provide the technician with DTC P0037 and reference Karma bulletin TB-18-12-05.
  • Do not attempt high-voltage-system repairs based on this code; no high-voltage repair procedure is established by the supplied evidence.

10. Step-by-step troubleshooting

  1. Inspect the secondary O2 sensor wiring for correct routing.
  2. Check that the applicable wiring clips are properly attached.
  3. Inspect the secondary O2 sensor connector for water ingress.
  4. Replace the sensor as needed, then route the O2 sensor properly, as directed by the bulletin.

11. When to contact service

Service is recommended for inspection and correction under Karma bulletin TB-18-12-05. The supplied evidence does not establish urgency, drivability limits, or charging limits.

12. What the service center may check

  • Confirm the vehicle is a 2018 Karma Revero for the North American/US market.
  • Confirm stored DTC P0037 and evaluate any associated O2-sensor-related DTCs.
  • Inspect secondary O2 sensor wire routing and clip attachment.
  • Check the secondary O2 sensor connector for water ingress.
  • Replace the sensor as needed and ensure proper routing.

13. Possible repair or resolution

  • Correct the secondary O2 sensor wiring routing and clip attachment if needed.
  • Address water ingress at the connector if found.
  • Replace the secondary O2 sensor as needed.
  • Route the O2 sensor properly after service.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Karma TB-18-12-05, published November 20, 2018: applies to MY18 Revero vehicles in North America presenting with associated DTCs. It covers inspection of O2 sensor wiring routing, clip attachment, and connector water ingress for P0036 and/or P0037, P0138, and P2270.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Official source: NHTSA Manufacturer Communication PDF 10152395, Karma TB-18-12-05: https://static.nhtsa.gov/odi/tsbs/2018/MC-10152395-9999.pdf

19. Frequently asked questions

What does P0037 mean on a 2018 Karma Revero?

It means “HO2S Heater Control Circuit Low Bank 1 Sensor 2.”

What should be inspected for P0037?

The official bulletin directs inspection of secondary O2 sensor wiring routing, clip attachment, and the connector for water ingress.

Does the bulletin call for sensor replacement?

Yes. It states to replace the sensor as needed and route the O2 sensor properly.

Is P0037 covered by a recall?

Not yet established by verified evidence.

20. Sources & verification

ReferenceVerified
Karma P0037: HO2S Heater Control Circuit Low Bank 1 Sensor 2 | EV Diagnostics