P0037 on Toyota
HO2S Heater Control Circuit Low (Bank 1 Sensor 2)
P0037 on Toyota vehicles indicates ho2s heater control circuit low (bank 1 sensor 2). Au7o has documented this code across 1 Toyota model — most commonly on Camry. The PCM detects low voltage (short to ground or open) in the heater control circuit of the downstream O2 sensor on Bank 1, Sensor 2. Typical repair costs on Toyota range from $90 to $350, depending on the specific model and root cause.
Common Causes of P0037
- •Open/short to ground in heater wiring
- •Failed O2 sensor heater
- •Corroded connector
- •Blown fuse
P0037 on Toyota by Model
Toyota Camry(2 issues)
- Upstream Air/Fuel Ratio (A/F) Sensor Failure — Heater Circuit Fault and Lean/Rich Codes2007-2017
Toyota's upstream wide-band Air/Fuel Ratio (A/F) sensor (Bank 1, Sensor 1, mounted before the catalytic converter — Toyota's name for the front O2 sensor) is a well-known wear item on the Camry. The internal heater element or sensing cell degrades, setting heater-circuit and lean/rich codes, illuminating the check engine light, and causing rough idle, hesitation, and reduced fuel economy. It is a frequent FAIL item at emissions testing.
- P0606 'Ghost' ECM/PCM Code Disabling VSC/TRAC — Actually a Rear O2 Sensor Heater Fault2006-2012
Camrys of this era commonly set DTC P0606 (ECM/PCM Processor) together with the VSC, TRAC OFF, and check engine lights. Despite the code pointing at the computer, the real cause is almost always a failing downstream (rear) oxygen sensor or its heater circuit confusing the ECM. Many techs have needlessly replaced the ECM. Toyota documents this pattern, and replacing the wrong part wastes hundreds of dollars.
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View P0037 across all makes →Frequently Asked Questions
What does P0037 mean on Toyota?▼
P0037 stands for "HO2S Heater Control Circuit Low (Bank 1 Sensor 2)." The PCM detects low voltage (short to ground or open) in the heater control circuit of the downstream O2 sensor on Bank 1, Sensor 2. On Toyota specifically, this code is documented across 1 model.
What causes P0037 on Toyota vehicles?▼
Common causes on Toyota: Open/short to ground in heater wiring, Failed O2 sensor heater, Corroded connector, Blown fuse. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0037 on a Toyota?▼
Repair costs on Toyota range from $90 to $350, depending on the specific model and root cause.
Which Toyota models have P0037 documented?▼
Au7o has documented P0037 on 1 Toyota model: Camry.