Auxillary water pump for turbo

Talk and Tech about turbocharged 924/944/968 cars
dds28
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I just linked your video on Rennlist where I had also posted a thread in the 944 turbo forum.

#11

mikee30
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I had a similar issue and here is how I tackled it.
My test procedure was first to ensure the motor was getting power by grounding out the sensor (in my case the motor would run).
I had limited testing equipment so I opened my relay to visually inspect capacitors and took readings of the resistors. Everything looked fine, but since I had trouble sourcing a replacement relay, I just replaced the timer IC in the relay and the issue was solved. The IC was 1-2$ if I recall correctly.

#12

dds28
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Where did you purchase the timer IC from and how difficult was it to replace it?

#13

dds28
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Just to update, I replaced my relay with one bought on ebay. Now the aux pump works again. Thank you everyone for your help.

#14

mikee30
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Just a note - if the relay for the waterpump aux motor is dead, before buying a replacement, you can try replacing the Timer IC on the relay circuit board for ~1$ (555 timer IC if I recall correctly)

#15

dds28
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mikee30 wrote: Fri Dec 01, 2023 12:12 pm Just a note - if the relay for the waterpump aux motor is dead, before buying a replacement, you can try replacing the Timer IC on the relay circuit board for ~1$ (555 timer IC if I recall correctly)
Thank you for the info. I will go ahead and buy the Timer IC and replace it on my old relay and see if it fixes it.

#16

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grantm951
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I bought a 555 chip from digikey. I haven't made the repair yet.

#17

dds28
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How difficult is it to remove the chip and solder it to the board? Any special equipment needed?

#18

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whalenlg
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It’s pretty easy. Generally solder, a soldering iron, solder sucker and some solder wick is all you need. Assuming that it’s a plastic 8 pin dip package.
1986 951 - Silicon Valley

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