A transmission pressure switch is reading out of range, so the module cannot confirm the pressures it is commanding.
P0871 — also written PO871, P 0871, 0871 — is the OBD-II code for transmission fluid pressure sensor/switch 'c' range/performance. Same code, same fix: this page covers every spelling of it.
P0871 is a transmission fault code, typically costing £180–£1500 to put right in a UK garage.
What causes P0871?
- Low fluid level
- Blocked filter restricting flow
- Failed pressure switch
- Internal leak in the valve body
How P0871 is fixed
- Check fluid level at the correct operating temperature
- Fluid and filter service
- Replace the pressure switch or valve body
P0871 repair cost in the UK
Most P0871 repairs land between £180–£1500 including parts and labour. The spread is wide because the cheap fix (a sensor, a hose, a leak) and the expensive fix (a major component) throw the same code — which is why a proper diagnosis before parts are bought saves the most money.
Can you drive with P0871?
Drive gently; avoid towing and motorway speeds.
Urgency: high.