I have the EPS problem, but no codes are coming up. Please help!

[Rufus]

I had a chance to start the NSX today. I started the car and let it idle for a bit while I reset the clock and the FM radio station memory (since those there all cleared out the last time I reset the EPS with the clock fuse). Then about 3-4 minutes sitting there idle, the idle RPM dipped to almost zero then the engine catching again. It did not stall, but almost stalled. When I looked up at my dash, the EPS light was on. The battery dial was moving back and forth between 12-14V.

It looks like the EPS shut down again. Since I wasn't moving (like the last time), the shutting down of EPS might have been more noticeable with the engine RPM dropping then going back up.

Anyway, I just wanted to write this up in case anyone had thoughts about this. I am now going to read through the instructions on how to get the error code (paper clip trick). Hopefully the error code will shed more light. Wish me good luck since I have never done this before.

 

[Rufus]

OK. Just did the code thing.

Few things to note for those who might have a 95 (or newer) model (or maybe this applies to older models too): My blue connector was easy to find - it was just at the top of the footwell where some other wire/connectors were visible. But problem was that the connector was mounted to a metal frame by a red plastic tab (not loose, tuck away somewhere like I was expecting). Looking at the photos posted, I see that the connector was dislodged and you can still the red plastic tab still connected to the connector. So I tired to rip (and basically) break off that plastic tab off the metal frame (without breaking the connector itself). After a couple of minutes trying to do this, I noticed a clip on the wire side of the connector. When I pressed it, it unclipped, allowing the wire-side of the connector to release from the rest of the connector that was still attached to the metal frame. The unclipped portion looks about half the size of the whole connector shown in the photos I have seen, but it also had two holes to put the paper clip into.

I write this up for those who might have cars that have this connector mounted right above the foot rest. You only need to unclip the connector to place the paper clip and then when you are done, snap it back into the housing (which is mounted to the metal frame). This is really convenient since I can now find my service connector easily as it is secured to a metal frame/bracket. Just clip off and use. I almost made this harder for myself.

So the paper clip service "trick" worked. All lights that stayed on did not blink. The only light that was blinking was the EPS light. I got two long and two short like laclipz. I guess I need to contact briank.

 

[Rufus]

I haven't made contact with [MENTION=7588]Briank[/MENTION]. Maybe he will see this post. I tried email, but will try PM.

 

[Old Guy]

I had a chance to start the NSX today. I started the car and let it idle for a bit while I reset the clock and the FM radio station memory (since those there all cleared out the last time I reset the EPS with the clock fuse). Then about 3-4 minutes sitting there idle, the idle RPM dipped to almost zero then the engine catching again. It did not stall, but almost stalled. When I looked up at my dash, the EPS light was on. The battery dial was moving back and forth between 12-14V.

It looks like the EPS shut down again. Since I wasn't moving (like the last time), the shutting down of EPS might have been more noticeable with the engine RPM dropping then going back up.

Anyway, I just wanted to write this up in case anyone had thoughts about this. I am now going to read through the instructions on how to get the error code (paper clip trick). Hopefully the error code will shed more light. Wish me good luck since I have never done this before.

Going back to your earlier post, I don't think you have a stalling problem because you have an EPS problem. I think more likely that you have an EPS problem because you have some kind of electrical problem that also caused the car to almost die. A serious internal problem in the EPS could cause a short that would cause the car voltage to dip and stall the engine; but, that has to be a big problem which would also blow the main EPS fuse. Since you haven't reported that I am going to speculate that you might have some external problem that is triggering the EPS shutdown.

 

[Rufus]

Yeah, you might be right that the root of the issue is some other electrical issue that is causing the EPS to shut down as well as the car to stall. Or it could be two different issues.

Last weekend when I took the car out for an hour and a half, the car functioned fine (with no power steering). I actually can't really tell that I don't have power steering until I'm pulling into the garage. The car definitely does not just stall on it's own while moving or idling. In fact, since I have been turning the ignition to position 2 for a few seconds (to allow fuel pump to power up) and then starting the car, it has been starting fine without stalls.

Two things I have noticed: The moment EPS light came on, I noticed that the battery gauge was moving back and forth between 14V and 16V. Looked like something was drawing enough current to make that gauge move. Not sure if that's normal or indication of other electrical issues.

The other thing I noticed (within the first mile of driving - car still warming up) was that the oil pressure was up to around 6. Then a minute later, I noticed it down to around 2 and then it settled at 4 (midpoint of gauge) and stayed there for the rest of my 90 minute ride (at least whenever I looked at the gauge). Normal? Indication of anything?

BrianK got back to me about the EPS module. I am going to work on removing it this weekend and sending it to him for repair. Ultimately, the root of my issue may be something else electrically, but I need to start eliminating possibilities. So I will start with repairing the EPS module since it worked out for laclipz.

Thoughts and suggestions welcome!

 

[Old Guy]

I am thinking alternator / voltage regulator problem. The voltage might dip a bit with a real heavy load or if there was a short. Rising to 16 volts is a sign that there is some significant problem and that your battery is going to be dead pretty quickly if that occurs often. On my car, there is no perceptible movement in the needle on the voltmeter. It could be glued in place for all I know.

 

[Rufus]

Sorry @Old Guy. That was a typo. My battery gauge usually is frozen at 14V. When the EPS light first turned on, the battery gauge fluctuated between 12V and 14V (not 16V). This happened while I was idling. Once I start moving, it locks onto about 14V.

I had a chance to drive the car for about an hour today. I tried to pay attention to the gauges today.

Car started fine. Turned to position 2 for about 3 second before starting the car. Car started fine. No stall or bobble. Engine sounded good. Battery went right to ~14V and stayed there the whole ride.

While the engine was warming up, oil pressure is at 5 or 6. Once the engine warmed up, the gauge goes down to 4 and pretty much stays there except when I go into neutral and idle. When I do that, oil pressure drops to ~2. Once I start moving again, it goes back up to 4. This seems like the correct operation to me.

So from what I can observe, everything seemed to be working tonight. All the gauges seemed to be working properly and measuring the right things. The only thing not working properly was that the EPS light was on since I haven't reset it and power steering was not working (as expected). I'm actually getting used to not have power steering. It's not too bad. I guess it's like having a 91-94 model. Anyway, BrianK is going to help me fix the EPS module. So hopefully, after that, all is good.

@laclipz, it sounds like you were still able to drive the car without the EPS module installed (while it was with BrianK). Can you confirm? I would like to know if I can drive the car while the module is away. Thanks.

 

[laclipz]

Yeah, you can drive it no problem. It just doesnt have power steering.


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[Rufus]

Wow, that's way more effort than I had hoped - to remove the EPS amp. The steps to get it off wasn't too complicated, but some of the bolts are really difficult to reach and with the set of tools I had, it was difficult getting the right angle to get the bolts off. But I got it off. I just hope I will have the angle to get it back on securely again.

I hope BrianK will be able to fix this.

Thanks for everyone's help.

 

[Rufus]

I wanted to give you an update on my EPS unit. I had my unit shipped to Brian K who repaired the unit and sent it back to me. Unfortunately, when I got the unit back, my temperamental ignition switch gave up and I could not start the car to test the new EPS unit until now (I finally got my new ignition switch - more about that in the other thread).

Everything is running great. I got my power steering back. No EPS light. Thanks [MENTION=7588]Briank[/MENTION]. And thanks to [MENTION=11893]laclipz[/MENTION] and [MENTION=26435]Old Guy[/MENTION] for your help and recommending Brian K.