[e92Kim]

Originally Posted by mainbearing

[correction: I meant X8683 above, not X6035, as X6035 needs to be connected to the pump while the fuse is out]

Backtracking a bit — with the pump disconnected, if you have measured open circuit ("1") on the Red wire, with the fuse still removed, plug the water pump connector back.

Then with the black probe to chassis ground, put the red probe at pin 2 of the 50A Fuse (X8683 end of the socket). Is there connectivity to chassis ground from the fuse now? (which earlier caused a fuse to blow just plugging it in).

If there is connectivity to ground now, remove the water pump connector again and do the same measurement (fuse pin 2 to chassis ground).

If now you measure open circuit ("1") then I suspect the water pump is bad with an internal short.

If so then test Pin 3 on the water pump to ground.

it tested “0” with the water pump unplugged and “1” without it plugged. Could this just be a fault in the water pump causing it to short? also i did say that the connector had a lot of oil/coolant in it when i pulled it out, i tried cleaning it the best i could but still no luck. Could this just be a bad connector/ wire?
Also when i tested X6035 all were “1” besides pin 4 it was “0” should i try tracing the wire for pin 4 to see if all is well and nothing is interfering with the wire?

[gbalthrop]

Originally Posted by e92Kim

I tested F03 without X6035 and it tested “1” and when i plugged it back in it was at “0” ohms.

Please remember I can't WATCH what you do, so I have to UNDERSTAND (correctly ;-) what you write. My understanding is that you Tested Continuity to Ground:
1) at the F03 Socket, with X60571 connected & X6035 DIS-connected, & meter read "1", or Open Circuit (NO Short).

2) You then CONNECTED X6035 connector to Pump, & meter read "0" Ohms, measuring at F03 Socket as before, indicating "Continuity"/ a SHORT-to-Ground.

If that understanding is CORRECT, there IS a short, but it MAY be due to movement of the wire when attaching the connector, rather than in the Pump.

A) Since you now know HOW to test for "Short", try to devise a way to TEST the wire at the Connector (X6035/3, Red wire) with X6035 DIS-connected from Pump, by Manipulating/Jiggling the wire as you measure for "Continuity to Ground" (Fuse F03 REMOVED). Remember that AS LONG AS POWER DISCONNECTED from wire (F03 removed), it is SAFE to test that wire.

B) You can ALSO measure Ohms at the Pump Pin that the Red wire of Connector X6035/3 connects to (with X6035 DIS-connected). Measure Ohms with Red Meter Probe on that Pump Pin, & Black Meter Probe on good Chassis Ground. Repeat Test with Black Probe on Pump Pin #4, which is OTHER large pump pin. Record/Report your Ohms Readings, along with the Ohms Range (e.g. 2k Ohms) selected on your meter. Make sure the "dot" or "decimal point" position is reported correctly.

ANYONE done this test? Got a known-good Pump lying around that you can test? Test Ohms Resistance between TWO LARGE pump pins.

C) There MAY be a Fault in the X6035 connector itself where there is "Intermittent Continuity" between sockets #3 (Red wire) & #4 (Brown Chassis Ground wire). Test with one meter probe on socket #3 & other on socket #4, as you manipulate the wiring & connector.

Hang in there -- YOU can FIND the short location & SAVE $$$$ if you think about it.
George

[gbalthrop]

Originally Posted by e92Kim

... Also when i tested X6035 all were “1” besides pin 4 it was “0” should i try tracing the wire for pin 4 to see if all is well and nothing is interfering with the wire?

The "Boggle Factor" is considerable when starting to understand wiring, 'cuz you CANNOT see the electrons, & have to get CONCEPTS of what is going on that WORK for YOU.

When testing Ohms/resistance in relation to Chassis Ground at the four sockets of X6035, there SHOULD be "Continuity to Chassis Ground" ("0") at X6035/4 (Large Socket #4, Brown wire), as THAT Brown wire connects to the Chassis to supply Chassis Ground to the Pump. See the 3rd ISTA ScreenPrint attached to Post #15 above.

CONCEPT: ALL Brown Ground wires connect to Chassis, which is connected to Battery (-) Terminal/ Post. That completes the "CIRCUIT" by returning electron flow to battery:
https://www.google.com/search?q=elec...hrome&ie=UTF-8

Please review the suggested tests in my post #24, and let me know if anything is UNclear.
George

[mainbearing]

I tested F03 without X6035 and it tested “1” and when i plugged it back in it was at “0” ohms.

Also when i tested X6035 all were “1” besides pin 4 it was “0” should i try tracing the wire for pin 4 to see if all is well and nothing is interfering with the wire?

Pin 4 of X6035 is the brown wire, so that is ground. That sounds ok.

As gbalthrop mentioned in post 24, you can wiggle the wires and see if the continuity changes. Sounds like you have disconnected and connected the wires enough times too.

I would also suggest you test the connector >on the pump<, which I have not read so far. Test where Pin 3 of X6035 (red wire) goes on the pump and chassis ground. See what resistance value you see there. You may need to dial the multimeter to 200-ohms range (I do not know what the Pin 3-4 resistance of the pump is).

My guess still is a bad pump, but you need to verify. You should consider buying from FCP Euro with their lifetime replacement warranty. I mostly use Rock Auto or RM European, just standard warranty but that is fine with me.

I just hope no damage was done to the engine with the overheating.

[e92Kim]

Originally Posted by mainbearing

Pin 4 of X6035 is the brown wire, so that is ground. That sounds ok.

As gbalthrop mentioned in post 24, you can wiggle the wires and see if the continuity changes. Sounds like you have disconnected and connected the wires enough times too.

I would also suggest you test the pump connector, which I have not read so far. See where Pin 3 of X6035 (red wire) goes on the pump and chassis ground. See what resistance value you see there. You may need to dial the multimeter to 200-ohms range (I do not know what the Pin 3-4 resistance of the pump is).

My guess still is a bad pump, but you need to verify. You should consider buying from FCP Euro with their lifetime replacement warranty. I mostly use Rock Auto or RM European, just standard warranties but that is fine with me.

I just hope no damage is done to the engine with overheating.

I’ll test the pins on the pump when i get home. The pump does have a lifetime warranty aswell as the thermostat i just didn’t want to have to replace it again, i’m very limited to tools in my garage and it was a pain in the ass last time. The pump was working perfectly fine besides the heat not working till driving the car around for like almost an hour and only when stopped. It started leaking coolant from what looked like the water pump and at that time i had a code 348A (Map thermostat: clamped open.) and that’s when the water pump stopped working. My cars also lowered pretty low so i’m not sure if from bottoming out could have caused any damage to the water pump ( i don’t recall bottoming out when it happened but has happened before)

[mainbearing]

348A stuck open thermostat will give you the no-heat condition even if the pump is working. Either there is a control fault or sounds like you have some questionable parts in there.

I only replaced the unreliable factory pump and thermostat once, but using aftermarket Behr and Pierburg pump. It was a pain for me for sure. I get you do not want to replace them again, but it may become necessary. At least do the test first.

I could not remember if I got these off Rock Auto or RM Euro, but so far so good. I think BMW's big mistake was using electric pumps, which later they reverted back to mechanical. Just stupid.

If needed, use CRC Electric Cleaner on the connectors, make sure to fully air dry before you plug things back up.




CRC cleaner:
https://www.crcindustries.com/qd-174...aner-11-wt-oz/

[e92Kim]

Originally Posted by mainbearing

348A stuck open thermostat will give you the no-heat condition even if the pump is working. Either there is a control fault or sounds like you have some questionable parts in there.

I only replaced the unreliable factory pump and thermostat once, but using aftermarket Behr and Pierburg pump. It was a pain for me for sure. I get you do not want to replace them again, but it may become necessary. At least do the test first.

I could not remember if I got these off Rock Auto or RM Euro, but so far so good. I think BMW's big mistake was using electric pumps, which later they reverted back to mechanical. Just stupid.

If needed, use CRC Electric Cleaner on the connectors, make sure to fully air dry before you plug things back up.




CRC cleaner:
https://www.crcindustries.com/qd-174...aner-11-wt-oz/

Okay thank you, i’ll test them and clean them out again. If it fails i’ll just replace the water pump and thermostat, i’ll just have to tow it to my shop so i can get it on the lift and fully take it apart to take a closer look and clean all the oil on it