All codes › P0115
P0115: Engine Coolant Temperature Circuit
What it means
The computer sees a general fault in the engine coolant temperature sensor circuit.
Severity: Medium Wrong coolant reading can stop the cooling fans from coming on; watch the temp gauge.
Common causes
- Failed coolant temp sensor
- Corroded connector
- Damaged wiring
- Low coolant exposing the sensor
Most common causes first. Exact causes vary by make, model and engine.
Can I fix it myself?
Often DIY. Replace the coolant temp sensor with the engine cold and top up coolant.
Repair cost
SEEDED ESTIMATE Roughly $40–$210
Most likely repair: coolant temperature sensor. Diagnosis fees, taxes and other causes are not included.
| Line | Low | High | Basis |
|---|---|---|---|
| Coolant temperature sensor | $12 | $50 | Typical listed retail range, source |
| Labor 0.3–1 hr | $30 | $160 | $100–$160/hr, shop survey |
⚠️ This is an editorial placeholder range for this type of repair. It is not based on real invoices or licensed pricing data yet. Real ranges will appear here once enough reader invoices for P0115 are verified.
Verified reader invoices for P0115: 0. Share your repair bill to help build real costs.
Tools that can read P0115
- ScanFixAI: Pro $29.99/mo or $249.99/yr
- OBDAI: Annual PRO bundle $299
- BlueDriver Pro Next-Gen: $119.95 list ($99.95 sale seen)
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