FUEL RELAY PROBLEM

HI, I am Adam and i was new in this comunity. I bough Golf 1 1.8 (1990) but i have problem all looks ok but my fuel relay doesnt work. I try run fuel pump they runs good, then i try measure 2 wires(yellow-red, brown) from fuel pump to fuse box they also looks ok.  But after when i turn ignition on fuel relay doesnt click and also pump not working. Somebody can help me where can be problem? My fuse box looks similar as on picture. Many Thanks. Sorry for my english.

Is your car Carbed or Digifant Injections system?

When you turn your car from Key in to Run, the first position, the fuel pump should prime the digifant system for 4 seconds does this happen?

The digi-fuel pump relay is VW #191906383C
They are pretty reliant.  So I would suspect the
fuses prior as verify that your fuses f5 is good.
I would then say when you turn your car on to run not start, does everything else work as in headlights, horns Radio and such?

The fuel pump runs off the fuel pump relay and a tach signal from the Hall sender, once the engine is started.

If you have a Digifant then there are 2 fuel pumps one in-tank and one external.  So I would have to ask you to verify that your 12V and a good ground are getting to the fuel pump, the external is infront of the axle right hand side, where the intank is accessed from below the rear seat bottom.

Lastly I would inspect your major grounds for cleanliness and voltage drop from the battery to the Frame horn below the airbox left side, and from the frame to the engine.  Good Grounds are the bane of these guy's there is also a bonding wire from the Valve cover rear  corner on the right side as you are looking at it to the Coil bracket which needs to be there and cleaned.

I have a how to, in the archive section that show you where most of the ground points are on the 90 cabbies.
which links to:
Ground effects and the repair of your car. | VW Vortex - Volkswagen Forum

I think you should check the fuses, then the grounds, and I have had ignition switches go wonky more often than the fuel pump relay, but you also need to see if there is water migration in your fuse panel from Windscreen leaks or plugged rain drains. You can usually see corrosion on the fuses, and it is a good idea to remove and re-insert your fuses to verify that you are cleaning the contact points on all of them as well.

thanks for answer…i must check all of this… but i have another problem car dont want turns on …. i replace all spark plug all cable to them + coil and still dont have ignition. where can be problem?

have you please wiring diagram for my ecu? for all pins and please for all ground points i want check all.

Bentley and haynes has the pin out for the ecu.

Most of the grounds can be found here.
Ground effects and the repair of your car. | VW Vortex - Volkswagen Forum

Thank you... I dont have this software can you please makes me screenshots?

Adam_V said

Thank you… I dont have this software can you please makes me screenshots?

The link is to a url that if you can read this post it will work.  

If you don't have a Bentley or a Haynes, I strongly urge you to get one as the schematics are a good thing to have.

I will copy the digi this one time.

Thanks... I try this weekend all things after i write here what was new!

the Bentley has the pinouts by pin location on the plug.

Hi, today i try measure again i put into car new TCI-H unit and new coil … i try measure like on link i post … put ignition on and between 1 and 15 terminal on coil i have for 2 second 7V then if i pull out Hall sender connector (distributor) cable and try measure between 1 and 3 pin… i dont have any voltage V28-0394 (https://workshop-manuals.com/volkswagen/golf-mk1/power_unit/k-jetronic/ignition_system/ignition_system_glow_plug_system/safety_measures_for_tci-h_system/checking_tci-h_switch_unit_and_hall_sender/) where can be problem? between coil and Hall sender connector? or i do something bad? thanks for answer…. and yes car dont have any ignition from coil when i trying put on engine block where was ground.


MY ecu was digifant 2

The hall sender has 3 wires, one red one not red and one green/white.

Remove the Rubber boot on the hall sender.
Place a DVOM between the green/white wire, and
the other on earth. Make sure the thing is still plugged in to the diz.

With the ignition on, in the run position.

If you note where the window shutter is prior, then loosen the dis clamp bolt, and what for the meter to go from 0-11Vdc….if this happens then your hall sender is good.  Now the funny thing on a DIgi-Fant…when you go from low to high the fuel pump cycles.

I would then go to the ICM where the hall serder goes to.

ICM;s are only about 12 Bucks new over here.

Hi bros, first sorry for late respond...i have lot of work (you know home,garden...) i measure conectivity between ecu and hall sensor all ok i replace ignition unit... And i checking it and it looks bad ECU digifant 2. Because i dont have spark and not hear fuel pump. Can somebody give me advice? It can be bad ECU? And what components can be bad inside?

Somebody ???

With the key in and the key moved from insert to run (1st position) there is no signals needed for the fuel pump relay to engage, and prime the system outside of the Digifant Controller to work.  I would also verify that your coil is good, as you didn't say that when you were cranking your car what the tach was doing.

So start at the basics first, check your fuses and fusible links to verify that the battery is supplying 12V to both sides of f1, as that is the first thing I would be checking if the fuel pumps didn't prime, and work back from there as it could be as simple as a Fuse, Fusible link, or the ignition switch.

You might want to buy a Haynes or a Bentley.

if its a factory digifant you should have a 53 relay in slot 1 which powers the ecu. check this clicks ignition on, look at fuses 17 and 18 one of those is for the relay ignition trigger

you can switch the 17 or 18 relay from your fusebox into slot 2, this should make your fuel pump run with ignition on. (load reduction, in the socket underneath fuel relay) does the car start when you do this?

there will be a connection in the scuttle somewhere between the ecu loom and fusebox loom, check the connections here for corrosion as usually they are open spade plugs up to 1990.

on the ecu loom connection(s) you will have some or all of these wires:
black/yellow - main ecu relay power
red/yellow - earth trigger for pump relay
green/red - starter cranking live to ecu
red/black - fuel injector power (sometimes not there, jumped to ecu relay power instead)
red/white - lambda heater power (from fuel relay, only used if it has lambda)

Thanks for answers i check all this things this week! please stay tuned! Many Thanks.