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EPS failure

Brian, I got these, NM and NC from old threads about EPS failures. They said to replace them. Tried changing relays in module like you suggested, but didn't work. thanks
Sorry Brian but I don't remember , it was last fall and a friend did it and he can't remember either. I'll try to get codes again. Will changing the speed sensors work or am I fighting a losing battle. Thanks
Changing the relays is really the only repair you can do short of buying new parts. If the relay replacment was done and did not take care of the problem its likelly your will need a new steering rack. Transmision speed sensors provide signals for the ECU, transmision control unit, EPS, and ALB so if one is bad you should be having other problem then just with the EPS.
FYI -my battery died (tiny race battery) the other day and my EPS light was on after and my EPS was no where to be found.

Pulling the clock fuse has fixed it nicely, but I drove around for a few days before I fixed it.

Man, I love my power steering. I see no downsides to having it. The only time when it is readily apparent is when youre trying to park, driving slow, etc..

I had a tough time parking the car correctly in tight places without it. Im thrilled to have it back and do not believe that it is overly active when it matters.
As soon as I took my clock out and replace it was a monitor, my EPS light came on. I tried to reset it but without success.

Was this perfect timing with my monitor going in and the EPS going out or do you think they have something to do with one another?

Apologies to Briank, please do not take offense, I disagree with you on a few points here. I realize that there are two different people asking questions here, but I think both rykev16 and ARFNSXTC can benefit from this discussion.

The EPS will not reset when you turn the car off and back on. To reset the EPS, you need to remove and replace the clock fuse, as depicted on page 85 of the 1991 NSX Service Manual. (Right-click and open in a new browser window.) The locations of the speed sensors are depicted on pages 435 and 476 of the service manual.

As soon as I took my clock out and replace it was (sic) a monitor, my EPS light came on. I tried to reset it but without success. Was this perfect timing with my monitor going in and the EPS going out or do you think they have something to do with one another?

Yes. Since to reset your EPS you remove and replace the clock fuse, it seems logical to deduce that if you have eliminated the clock you may have affected or broken the EPS circuit. Since the EPS failed concurrent with the clock removal, have you checked the clock fuse to see if it is blown? If it was intact, I would reinstall the clock to see if that has any effect. Did you cut the clock connector?

It is possible to have a bad speed sensor that is affecting only the EPS. When I was having this problem, for a year or so the EPS would only drop out occasionally, but when the speed sensor got worse it started affecting other systems and the EPS was staying off all the time.

If all else fails, I have a used (not rebuilt) EPS module laying around somewhere that we could try. (Why do I have an extra EPS ECM lying around? Because I bought a used one when my EPS was giving trouble, but that turned out to not be the problem.

Let's work the simple things first. To summarize, here is what I would do, listed in order:

a. Check your clock fuse. Even if it appears intact, try replacing it with a new one of the correct amperage.
b. Reconnect your clock if it is disconnected. (This will also tell you if the clock fuse is good.) If you have cut off the connector, you will need to directly splice the wiring together.
c. Replace the NM speed sensor. (Although the listing says for '92-'05, this should fit your car. I realize that this speed sensor is "too cheap", but if we get your car sorted out you could later replace it with a higher quality speed sensor. So first we are going to try spending small money on troubleshooting instead of big money on steering racks. Nothing would suck more than replacing a rack and having that NOT be the problem.)
d. If we get this far, we will go from here...
y. I have a used EPS ECM that you could try. If it solved the problem, I would sell it to you for what I paid for it. If it didn't solve the problem, you could just send it back.
z. If you needed it, I even have a spare clock.

If you haven't already, I recommend downloading the service manual to your computer from this page. You may do this by going to section 1.1 Electronic Copies of the Service Manual, then right-clicking on the top link in that section and selecting "save target as" or "save link as" (depends on which browser you use), which will save a copy of the service manual to your computer. This downloads a .pdf copy of the service manual which is searchable. Simply enter "speed sensor" at the top and it will search for each mention of the words "speed sensor" in the service manual. You will find numerous mentions of the speed sensors as you search the manual.

Here is a link to my old thread on the topic. The EPS on my automatic is still rock steady after having replaced the NM speed sensor.

When either of you reply, please describe as thoroughly and as specifically as possible the problem(s) that you are experiencing with your EPS or other systems. I really want to help both of you get this sorted out and avoid buying unnecessary, expensive parts. Don't panic!! I don't think either one of you need a new rack. I think you just need to get some electronic gremlins sorted out.
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