Heater problems again
Heater problems again
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LenChim

Original Poster:

226 posts

176 months

Friday 9th April 2021
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Well, l I have toasted the connector on the heater ECU again. The heater blower motor runs but is noisy. I have had it out before when it fried the plug before, some 14 months ago, oiled the bushes, etc, it seemed to spin ok. I checked the current draw and came up with, Top speed 14 amps, Medium speed 8 amps, and low speed 2 amps. Now it must be said that I am measuring this with an old-fashioned but new +/- 30 amp dash gauge as my good meter will only handle 10 amps DC max and it was well over that. Now I have been told that the plug on the ECU will handle 16 amps and that the blower motor should only draw 8 amps.
So the question is, is there something wrong with the blower motor, should I wire it** so it only runs on the middle speed at max on the controller, or is it that the pins on the plug are not tight enough and have a poor connection thus causing the plug to fry? NOTE it has to be said that last time it was the black wire pin that burned and this time it was the yellow wire pin, this leads me to think it is a poor pin connection. ( Not tight enough).
Well oh wise people what do you think?
  • The plug that comes out of the casing where the blower motor has 4 pins, earth, and one for each position on the built-in resistance that is normally bypassed e.g. maximum speed.
:rolleyes

Penelope Stopit

11,209 posts

130 months

Friday 9th April 2021
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LenChim said:
The heater blower motor runs but is noisy
Explains why the terminals are getting hot

Seen figures of 8 to 10 Amps current draw at start up measured when testing a known good motor

Without checking information, read that blower motor fuse is 15 Amp

Belle427

11,117 posts

254 months

Saturday 10th April 2021
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Sounds like time for a new motor, not a job I’d wish on anybody but most likely the culprit it being noisy.

LenChim

Original Poster:

226 posts

176 months

Saturday 10th April 2021
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Ok since this is not the first time I have had this motor out it only took me 1 and 3/4 of an hour to get the little B****** out checked the current draw on the bench 16 amps as I said, oiled it up dusted it off, etc run it on the bench disassembled, no casing on made sure that the bearings are well oiled ran for 10 minutes plus 8 amps current draw. Reassembled the casing, put it onto the fiberglass top plate. (I have separated the top plate with the fan mounted on it from the front cover in the footwell, to give easier access). Then I put the fan back in the car. No front plate and checked the current draw 15 flaming amps!! So just that the fan will pull 15 amps loaded e.g. ahead of air that it has to push through the matrix/heating system. Could the matrix be blocked with dust?
If so how do you get at the matrix? I can see the underside of it and it looks quite clean but then it would. Do you have to take the heater box out? Has anyone done that? I bet it is a real horror to get out. furious