HSF-3, pump not working

[FrisbeeGTI]

Hi.
I've got earlier some problems with HSF2/3 pump. The pump was assembled in a wet location and the pump seized and started to blow fuse. Opened the pump, it was rusty inside but got it spinning and gave some lubrication for it, sealed the pump and assembled it again. I also soldered the dropping resistor mod on the board . It worked fine for a while.

But today it seemed to spray ok some time in the beginning of ride, and then stopped working. I didnt see the gauge light but is was sunny day and i'm not sure... Got home and noticed that when i put the ignition on (but not starting) the pump starts working (sounded noisy) and doesn't stop at all if ignition is not turned off. It did not matter if the gauge button was on or off. If trunk, power or gauge connectors were unplugged pump didn't activate at ignition on. The gauge button didn't give light anymore on or off. There is enough water+meth in the tank.

Took the relay away and put it back (the relay connectors had some rust), checked connectors and earth connections which were ok. Fuse was ok. After that the pump didn't activate at all anymore. When I put the FAV connector to SYS the pump doesn't activate (THRES and 95% give the light). Fuse is not blown. Tried to give straight 12v to the pump connectors from battery but nothing happens. IDC light is blinking properly when motor is running.

I have to open the pump again. But why was the gauge button light dead? And why the pump activated when ignition was turned on and continued to give noise? I'm just thinking what parts I have to replace. :confused:

[Richard L]

a seized pump bearing will demand very high current. I believe the relay contact is burnt. I think you should get a new pump and relay. I wouldn't blame the gauge button for this.

The system clearly stated the pump has to be trunk installed, hence we supply 6M of nylon hose. Why did you not follow the recommendation?

[FrisbeeGTI]

Ok, thanks for the reply.

Yes, I didn't follow the instructions and fault was mine. Actually I didn't notice that statement at first (maybe it could be stated more clearly in the instructions with big letters..) and installed the pump behind front bumber next to engine. Despite some problems I have been very satisfied with the system as whole and this support site is superb.

[FrisbeeGTI]

Well..

I tested the pump resistance and it was about 3-9 ohms (i've got a low quality multimeter). Next thing to do was to check again pump wirings earth connection, it seemed to be ok with that multimeter, but to be sure i wired the earth contact directly to battery -. After that I gave the pump 12v direct from battery via 20A fuse and it started working. Took off the pipe from FAV and the pump did good output to a container through that pipe.

Problem is now that when i put ignition on, the pump activates and doesn't go off at all. Gauge button light doesn't light up. Same thing with the pump gauge button on or off.

I tried with a another new automotive relay and the same problem persist. I think tomorrow I check all other earth connections (I took my engine out and put it back to do some things before last drive..)

Do you have thoughts what is wrong? Is this no-light-in-gauge-button issue somehow associated with the problem of pump working ad infinitum at ignition on?

[FrisbeeGTI]

Checked some important earth connections (cleaned up body-battery negative cable connection, wired directly battery - to HSF2 ground (white and black wires). Same problem remained, when I turn ignition on, pump activates and doesn't stop, when I started the car, IDC blinked and I turned treshold so that system injected, pump working all the time. Gauge button does not have light on or off. Checked that HSF2 gets 12v via power connector.

The TRESH light blinked once briefly on the board every time i put ignition on, and not after that, the pump continued to work.

I unplugged the water level sensor connectors, no change. Then I connected yellow and black wires (which connect to water level sensor) with each other. After that I TRESH light didnt blink briefly at all at ignition on, but pump activated and continued. When I started the car after that, the IDC light is not blinking anymore...

So somehow I probably destroyed also the board... :confused: Is that connecting directly yellow and black wires (which connect to water level sensor wiring) dangerous for the board?

Still at the end I tried the SYS -function (FAV jumper to SYS) and TRESH and 95% lights lighted up (pump was working allready because ignition was on).

Could it be any sensible mechanism in this problem?

[FrisbeeGTI]

This continues to be absurd, but just noticed that i have mixed up the gauge and ecu connectors with each other on the board connections.

Changed those connectors and gauge button begun to have light (first yellow some seconds and then green) and the pump doesn't continue to work after ignition is on. Next problem is that I don't have anymore IDC light blinking after I have started the motor. I don't understand how it was blinking earlier with wrong connectors on !!? If I remove the IDC connector the pump stars working when motor is running. Water level sensor wiring is not plugged.

Checked the injector connectors, red wire gets 12v when the motor is running, green wire is in injector -.

[FrisbeeGTI]

The reason for flickering of FIDC when GAUGE and ECU connectors were mixed up was that I had connected injector wires through the USER (green) connector.

Took out the USER wire and connected injector - (green wire) and 12v (red wire) through the ECU-connector but I don't get the FIDC flickering when motor is running. I checked the continuity between injector - and ECU connector and between 12v (red wire) and ECU connector. The board fuse gets 12v, tried also with another 5A fuse. No flickering of FIDC when motor is running. :(

Is the board now faulty? FAV connector -> SYS functions as it should I think (THRESH and 95% light up). When i pull out IDC-connector TRESH lights up and pump is activated.

Is it possible to fix up this board somehow anymore?

[FrisbeeGTI]

Well.. I put back the green cable (USER) and connected green wire to injector - and red wire to injector +, then connected ECU cable's red wire to 12v (pre-cranking). Result is that the system started to sense IDC and is now working OK, spraying W/M.

So I had the low impedance injector mod on the board (I have resistor pack for injectors), and in such situation it's adviced to use green USER cable with green -> injector - and red -> injector +. The system didn't work without additionally connecting ECU cable's red wire to 12v.

I'm sorry for this confusing story, I didn't recall at all what kind of assemblies I did couple of years ago. Still I hope that this helps to understand how HSF2 works. I think should be made impossible to mix up with GAUGE and ECU -connectors in future releases.