Fault code lookup

NetworkU3036

Serious

Severity: Serious - have it checked soon

Communication Authentication Signal Performance

2 brands affected · Generic SAE J2012 description.

Key terms: Control module: a small computer that runs one part of the car · SAE J2012: the standard generic code list

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 2

BrandCodeDescriptionSystem
Ashok Leyland CVU3036After Treatment 1 Inlet NOx Sensor Short/Open BrandNetwork
EOBDU3036Side autentimissignaali toimivus 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.

5Extended variant codes 2

These 7-character codes are manufacturer-specific variants of U3036 and may be reported by some scan tools.

BrandCodeDescriptionSystem
Mercedes-BenzU303657Communication Authentication Signal Performance - Incompatible Software Component BrandNetwork
Mercedes-BenzU303681Communication Authentication Signal Performance - Invalid tick count received BrandNetwork

6Related codes

Browse Uxxx codes or U303xx codes.

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