DTC code definition (E-OBD)

In order to brush up on the rules governing the handling of modern cars, with this post we begin to publish a short series of 'technical tidbits' that we believe will be useful in better interpreting situations that occur in the workshop on a daily basis.

Let us begin by recalling the meaning of the acronyms:
DTC: 'Diagnostic Trouble Codes'.  i.e. "diagnostic fault code"
EOBD: European On Board Diagnostic i.e. 'Diagnosis on board vehicle version Europe' (which is also used as a synonym for DTC)

Error Codes DTC (E-OBD) are divided into four different types depending on the car part involved:

P power train
B Body
C chassis (Chassis)
U future systems or undefined errors (Undifined)

The second digit represents the subgroup to which it belongs:

1=Fault code reserved for the manufacturer
0 or 2= SAE standardised fault code

Here are some examples of SAE standardised error codes

P0130 Lambda sensor circuit1 bank 1
U2007 audio navigator not responding

Here are some examples of manufacturer reserved codes

P 1629 Daewoo/Chevrolet:  ECM control unit has received incorrect messages from the immo system more than 5 times; starting is not allowed
C1091(Ford) Inconsistent vehicle speed signal
B1201 (Ford) fuel level signal error

Of course, by nature of the Tech Blog, we remain at your disposal for any questions and look forward to seeing you next time... ciao   

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