Intermittent immobiliser issue

[jonski1987]

Hi All, 

This is my first post, I bought a Focus 1.8 TDCI LX 2005 5 days ago. Unfortunately it has already developed an intermittent starting problem, which leaves me feeling worried I've inherited a known problem here. 

Intermittently, the car just doesn't start, and instead the immobiliser light blinks. At first I thought it was a flat battery as it was cranking but was weak. Then after leaving it for a few mins it started just fine? Then again, the following the day, when turning the key, absolutely nothing. Seemed like a complete flat battery despite radio working. Then a few minutes later it started just fine. 

As of today, car is working absolutely normal, with no immobiliser flashing/ weak cranking. Car just starts perfectly. 

This is really strange! Any ideas? 

JP

[JIMMWX]

Doesn't say how you bought it (trader, private) etc.

If it's a trader, have you spoke to them, since you say you've only had the car 5 days.

[jonski1987]

It was private unfortunately. 

Since buying it, I've also noticed it doesn't quite get up to normal temperature, in the middle of the gauge, instead it sits at 1/3. 

Any ideas to help troubleshoot the above two problems? 

JP

[Tdci-Peter]

On 04/01/2017 at 5:38 PM, jonski1987 said:

instead the immobiliser light blinks

The Focus IC (instrument cluster) in models around 2006 is very prone to faults. However yours may be before this. A likely cause is the link between the PCM (engine computer) and the IC. This is vital for the PATS (immobiliser system).

The PATS led should give a code, that will help identify the cause.

Typical flash code:  The red immobilsor light will flash rapidly for 1 minute then it will emit a code
Example - 1 flash -PAUSE - 6 flashes = flash code 16

Flash Codes:

1 : 3 Key code not received is the key obscured, try again with different key, key may be damaged/faulty

1 : 4 Partial code only received is the key obscured, try again with different key, key may be damaged or faulty

1 : 5 Key valid but not programmed to PATS

1 : 6 Faulty link between IC & PCM

If it is the PCM to IC wiring, I can help further with likely problem areas if needed.

Regarding the temperature gauge, my one sits about 1/3 of the way up, but it is the right temperature, as I have a separate monitor of coolant temperature. My thermostat is set for 80C, and that is what I see, once warmed up, though that can take quite a few miles in these efficient but rather heavy diesel engines.