Fault code lookup

NetworkU0623

Serious

Severity: Serious - have it checked soon

Lost communication with coolant pump 'A'

12 brands affected · Description from Toyota data.

Key terms: Control module: a small computer that runs one part of the car

Safety: This code relates to engine cooling or temperature. Overheating can damage the engine.

1What it means in plain English

Control modules in the car cannot communicate with each other over the vehicle network.

2Common causes

  1. Wiring or connector fault on the communication bus
  2. Faulty control module
  3. Low battery voltage or poor ground
  4. Water ingress in a connector or module
  5. Aftermarket device interfering with the bus

3Can I drive?

Serious · drive with care

The car may run normally or may not run at all. If the module that has lost communication controls steering, brakes, park brake, charging or engine cooling, drive only if those systems feel normal; stop safely if the steering becomes heavy, a brake warning appears, or the engine temperature climbs. If the car will not start or runs badly, have it towed.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 12

BrandCodeDescriptionSystem
Ashok Leyland CVU0623No description available Network
DaewooU0623No description available Network
EOBDU0623Förlorad kommunikation med kylpump 'A' BrandNetwork
GMU0623No description available Network
HoldenU0623No description available Network
Land RoverU0623Lost Communication With Coolant Pump 'A' BrandNetwork
OpelU0623No description available Network
PeugeotU0623No description available Network
SaabU0623No description available Network
SuzukiU0623Error status of AUWP LIN Node BrandNetwork
TataU0623No description available Network
ToyotaU0623Lost communication with coolant pump 'A' BrandNetwork

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Related codes

  • U0620 Lost communication with exhaust gas temperature sensor bank 1 sensor 2
  • U0621 Lost communication with exhaust gas temperature sensor bank 2 sensor 1
  • U0622 Lost communication with exhaust gas temperature sensor bank 2 sensor 2
  • U0624 Lost communication with coolant pump 'B'
  • U0625 Lost communication with fuel rail pressure sensor bank 1
  • U0626 Lost communication with A/C refrigerant pressure sensor 'A'
  • U0627 Lost communication with A/C refrigerant temperature sensor 'A'
  • U0628 Lost communication with A/C refrigerant pressure sensor 'B'
  • U0629 Lost communication with A/C refrigerant temperature sensor 'B'
  • U062A Lost communication with A/C refrigerant distribution valve actuator 'A'
  • U062B Lost communication with A/C refrigerant distribution valve actuator 'B'
  • U062C Lost communication with A/C refrigerant distribution valve actuator 'C'

Browse Uxxx codes or U062xx codes.

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