No Rad Fan After CE2 Swap

[jhax]

Hey Everyone,

Well the swap is done, the only issue I am having right now is the radiator fan. I swapped in the harness from a CE2 car with AC. I used all the original US electromechanical stuff (fan, thermo switch and hi and low pressure switches. I can't for the life of me figure out why the fan doesnt work. I pin swapped the ce2 fan wires to the US fan. It blows when I turn on AC, but the thermo switch doesnt seem to sense when to turn the fan on. Same with after running. The wire pin out from the thermo switch seems to be the same for both. I tested the thermo switch plug (jumpering wires) and only the high speed worked. Although when I turn the AC on low, the fan spins slow. What am I missing here?

Thanks,
Justin

[theman53]

It probably doesn't need to run. My fan never runs unless I turn the a/c on. Maybe if I let it idle for hours it would. I have a low temp t stat is mainly why but even when I ran a 195 stat it would hardly ever run more than 5 seconds.

[jhax]

Ohh man, mine needs it. I have a low temp thermostat too and that was a mistake. The coolant doesnt spend enough time in the radiator before cycling back into the engine so it runs warmer than it did. I drove maybe 4 miles today and my light was flashing and temp gauge was up. This is so frustrating.

[bajacalal]

That's not normal. The mk2s have good cooling. Mine takes forever to warm up to operating temp even on a hot California day. The people who live in Canada, I hear have to block the radiator in the winter. You have a cooling system problem, too small of a radiator or an electrical issue and no actual cooling problem. I remember my ce1 car would blink the light and run the temp gauge all the way to high to indicate the coolant level sensor on the tank was sensing low coolant. If you're still using the ce1 gauges it might not be getting the signal it's expecting.

[jhax]

My old 87 gti ran below the light. This one always ran on or just above the light. I didnt have CE1 I had the US electrical system. Any other advice?

[jhax]

and now thw damn car wont start...f***k. Glow plugs wont come on. I drove the car twice today. Fuel is in the feed line after gravity filling it. Fuel is getting to the injectors. No water in the filter or water separator.  I test the voltage during cranking at the battery (located in the hatch) and it drops to about 11.6V when I test the voltage during cranking in the bay I get 0V at the starter and my ground to the chassis (sandwiched between the front x-member bolt head (which bolts directly into the chassis) and the front cross memeber (holds the bumper on) what gives?

[jhax]

Re-grounded, chassis ground is now on the front most bumper bolt, (nut welded to the chassis), still doesnt start. Throwing in the towel for tonight.

[theman53]

You could re wire it. Run a positive from the starter to the temp switch and run the wires from there to the fan. Fuse it from the starter.

[jhax]

You could re wire it. Run a positive from the starter to the temp switch and run the wires from there to the fan. Fuse it from the starter.

Temp switch being the thermo switch? coolant temp switch on the front of the engine? The original wiring had BN/BLU and BN wires from the AC to a two prong (AC temp? ac cutout?) switch on the front of the engine (underneath the coolant temp sensor on the same coolant neck) the brown grounded to a ground collective (AC, wire from the trans plug to the head on the side of the block) and to the lo speed rad fan relay.


I have to get my car started before I can figure out my cooling issue.

[jhax]

I tried to start it again just now and nothing. I then took out the glow plug wire from the fuse box and turned the key to the on position, no voltage going to that pin at all. There is a voltage coming from the thermostat (1.4V), but nothing to the plugs. I used the original US glow plug wire (one big black wire that splits into two smaller wires in the cab and  to the relay.

[jhax]

So the starting issue was definitely the glow plugs. I jumpered the glow plugs and it started right up. The question is, where could the problem be within the system? I just realized that I never put in a fuse for the glow plug wire (the original US has a fuse thats attached to the relay block. Could I have possibly screwed up my ce2 fuse box by not putting in an inline relay? Also when I say my GP light flashes, it doesnt flash in any sort of pattern, it flickers randomly. It seems like the light its self is grounding out or picking up a signal. However there are no exposed wires anywhere.

[bajacalal]

My old 87 gti ran below the light. This one always ran on or just above the light. I didnt have CE1 I had the US electrical system. Any other advice?

Yes you did. You had the CE1 electrical system. There are 2 major electrical designs on the mk2 cars, CE1 and CE2. Yes, there are variants of each, Jetta vs. Golf, Euro vs. North American, some changes between years but 90+ % of the ce1 stuff is the same for any ce1 car.

From what I've seen, the needle slightly below the midpoint/light on the gauge of the ce1 cars seems to be where it normally should be. If it's higher than that I think you should check to make sure the cooling system is indeed working right and if you still have gauge that is high, there's an electrical issue, something in the cluster or bad ground maybe. I had the same thing happen on a ce1 car, random high reading on the coolant gauge, blinking light. It was the coolant level sensor in the bottle crapping out.

So the starting issue was definitely the glow plugs. I jumpered the glow plugs and it started right up. The question is, where could the problem be within the system? I just realized that I never put in a fuse for the glow plug wire (the original US has a fuse thats attached to the relay block. Could I have possibly screwed up my ce2 fuse box by not putting in an inline relay? Also when I say my GP light flashes, it doesnt flash in any sort of pattern, it flickers randomly. It seems like the light its self is grounding out or picking up a signal. However there are no exposed wires anywhere.

Not knowing more about what you did, it's hard to say. Where did you source the power for the glow plug relay, the system takes A LOT of amp draw somewhere around 40 amps iirc. I have observed my glow plug relay do the same thing when its not getting enough voltage (to the circuit that activates it, not the battery + feed). In my case it was just a dead battery.

[jhax]

http://www.a2resource.com/electrical/images/VWwiring.jpg 3 electrical systems, the US was not central since the fuse and relay blocks are not on the same block.

Glow Plugs:

The CE2 system has a glow plug terminal -Z1 (http://www.a2resource.com/electrical/CE2.html) that goes to the GP inline fuse and to the GPs The GP terminal on the fuse block gets its power from the main fuseblock power (Y/03). So Im not sure why it wouldnt work unless I screwed up the circuit by not putting in an inline fuse

Rad Fan:

After starting it and letting it run at idle and come up to temp, I took measurements at the thermo switch and got the following.

Idle...no AC (Temp gauge up to 3/4)

RED (Power) ----- 12.26V
R/WT (LO Speed) -- 2.35V
R/BK (HI speed) ---- 2.44 V

Idle... AC or Fan low speed Same with high speed inside the cab.
RED ------- 12.11V
R/WT ----- 13.98V
R/BK ------1.48V

Also, when the fan switch is turned on, the GP LED turns on and stays on.

I just got done testing the glow plug system (http://www.mikegabriel.net/vw/bentley/mk2/FU03/ch6.2.html) and it seems like something may be wrong. Here are my numbers.

87 to bus bar = 00.2 ohms (should be 0)
T and gnd = 0.66 ohms (does produce continuity below 122F)
30 and 85 =12.68V (correct)
50 and 85 = 9.5V and no glow plug light (should be 12V with light)
85 and 86 = 10.9V switched  (should be 12V switched)
Temp switch unplugged 11V at the bus bar (relay is fine) and glow plug light behaves

theman53: I made a wire connecting the starter to the RD/WT wire that connects to the thermo switch, hi pressure switch and fan, plugged in the fuse and the fan turned on (lo speed, ignition off) and it didnt turn off.

[theman53]

Kind of messed up. I think some of the wires are not what they are supposed to be. The thermo switch when wired like that should just cut the positive or not, shouldn't run all the time.

[jhax]

are you referring to the plugs or the fan?