Peugeot 306 fuel pump relay

[Mangarn]

Hi guys (and womens) . (sorry for my spelling, im from SWEDEN)

I try to help my friend with his peugeot 306 2.0 16v 1997 convertible.
He got it from his past away uncle, it has been standing still for 2 years.


Battery was dead, bought a new one and put it in.
Engine cranks but dont start.

I have found a problem with the double relay.
The side of the relay that starts the fuelpump dont get a negative signal. (pin 10 if i remember coreectly).

I have read so meny threads on different forums but cant find what cousing this problem.

I read somewhere that the negative signal should come from the ecu. I have found a cable from pin 10 in the double relay that goes to the ecu connection 0 ohms so the cable is okey.

I have checked negative connections in the Engine compartment, i have checked all fuses.

Fuel cut off switch works.

Eny ideas what to check next?

[Oldpug]

Hi Mangarn and welcome.
As the car has been standing for years and you have just fitted a new battery I`m thinking that the engine immobiliser has activated. Does the key fob work, can you lock and unlock the doors with it. If so do that a few times.
Also is there a small square button on the steering column cowling. If so hold the button in while turning on the ignition, the four ways should flash.

[Mangarn]

Thanks for answer .

The keyfob does work, pushed it several times but nothing new happens.

Ive read in some forum about the square Button but couldnt find one on this car . (dont have the old keypad Immo either)

The four way, What is that?

Tried to read more about the Immo, what parts does the Immo shut down if activated?


Ive tried to measure the cables and inputs/outputs from ecu but cant find a wiring diagram that match this ecu. Its a Bosch mp5.2

[Shredder11]

"Four ways" I assume means the orange direction indicator arrows, which is what happens on my 2.0 XSi if the battery is reconnected and the doors are not previously locked with the fob. I then have to press the square button on the right side of the steering column with the key in the ignition and set to accessories mode or something. You then press the fob to lock and unlock the doors and that stops the alarm and the flashing orange lights. However if you already have the doors locked with the fob, and then reconnect the battery the alarm does not go off and no flashing lights on the dash etc.

[Oldpug]

On right hand drive UK models this is the button. " 4 ways " is a term we use for the hazard lights, the four indicators flashing.

Its a very long time since I worked on 306`s Mangarm, I retired 15 years ago. From what I remember these old immobilisers were a pain in the butt for mechanics when working, disconnecting batteries and so on. I think the immobiliser kills the fuel pump. There is also a siren inside the left hand front wing. They always get filled with water and stop working. Another item I can remember is a key barrel switch located in the engine bay near to the battery. You insert a key ( not the ignition key) to turn off the immobiliser when working on the car. That key always gets lost or mislaid by the car`s owner adding to mechanics frustrations.

I`m pretty sure this immobiliser is your problem. Is it possible you can find in Sweden an "old school Peugeot mechanic" , who has had experience with old 306`s.

[Oldpug]

I realise I`m not giving you anything positive, I`m just trying to remember various items that suddenly causes these 306`s to not start.
I assume that the car was starting and running OK before it was put into storage. If its not the immobiliser it could be poor connections caused by corrosion due to lack of use. All you can do is clean all the earths, check all the multi plugs for "green" corroded connections. Also relays can stick or get hot. Check the small green one in the interior fuse box. Then there is a multi function fuel pump relay in the engine bay fuse box. Its like this one in the image.

I`ve had a few 306`s and 406`s that suddenly wont start, change this relay and they fire up again. There are many different types, so you must have the exact replcement.

[Mangarn]

Hi again .

Thanks for your support .

I went out and took another look, no square button .
No key barrel in engineroom.

Multifunction relay is working, took it apart earlier this weak. The ecu is supposed to send earth to the multifunction relay but doesnt. If I put earth to the relay the fuel pump works.

I sprayed starting gas in the inlet and I got it to combust but no fuel.

I think this car dont have an original mounted alarm because there is an aftermarket alarm installed in sweden. I have done some tests and If I tigger the alarm it wont crank, then i push the fob to deactivate alarm and it cranks again.

I tried to get in touch with Swedish peugeot old school mechanics in different forums but got no luck..
Googled for answers and find most forums from UK.

Ive cleaned and measured every earthconnections in engineroom without luck

[Mangarn]

ello!

New input.
Measured at the ecu today, the ecu is missing +15.

Eny clue where that cable may come from?

Ignition switch on - to some pin somrewhere - ECU.

[Mangarn]

Take a look at pin 34 at the ecu.
+15* no clue what the star means .

IF this is a switched live to the ecu, its missing.
Where could i search for the other end of the cable?

[Mangarn]

https://ibb.co/ww1J8Ny

[Mangarn]

Measuring today, I got +15 at pin 34 ..

Now is the biggest question why I dont get an negative signal from ecu pin 3 to pin 10 on double relay?