friend has a 2007 Octavia that has a repeatable fault with starting.

 

if the ignition is left on or its a hot day/car hot, when the keys is turned the engine just spins. if the ignition is left off for a few minutes it will generally start.

 

when using my vcds cable, during the non start period I cant get any coms from the engine ecu.

 

I wonder if it is the 109 relay prob. but we cant find it. looked under the drivers foot well but cant see a relay with that number.

 

the 2 errors we get are:

 

005633 - Relay for Supply Voltage Terminal 30 (J317)    on the engine ecu.

 

and

 

01314 - Engine Control Module      on almost all the other ecu's.

Edited 8 May, 20179 yr by cypher007

Caused by low battery voltage. Read the battery voltage with VCDS or a multimeter.

From what I remember, starting is inhibited unless a certain cranking speed is reached (500 rpm?) when hot, so low voltage from the battery or poor connections at starter/ground.

 

Have you tried jumper cable starting from another car/battery?

Edited 8 May, 20179 yr by pikpilot
Typo

new battery was fitted and still doing it.

 

its like something is overheating?

ok got a bit more info:

 

when it will start the engine light comes on and esp comes on briefly, after starting engine the engine light goes out.

 

when it wont start the esp light stays lit and there is no engine light.

anyone?

 

wheres the ecu on these?

Edited 16 May, 20179 yr by cypher007

On 11/05/2017 at 14:01, cypher007 said:

ok got a bit more info:

 

when it will start the engine light comes on and esp comes on briefly, after starting engine the engine light goes out.

 

when it wont start the esp light stays lit and there is no engine light.

I have this same issue, first time my spare key solved it but then it happened again and now both keys won't do the trick.

 

Did you find a solution?