Starting problems - ignition switch?

[PeterW]

In August 2021 I posted a thread reporting a starting problem which I thought I'd fixed by replacing the main relay. The symptoms were that the engine would turn over and fire, but would then die. http://www.nsxcb.co.uk/showthread.ph...ighlight=relay The relay I took out had been resoldered, and I figured that the resoldering had failed. Unfortunately I'm still having the same problem, even with the new relay, so it seems unlikely to be relay problems.

Typically it takes three or four attempts before the car will fire up and keep running, but after that it runs normally.

On one occasion after I'd got the engine running, the TCS amber warning light stayed on until I turned the engine off and restarted it. I get error code 35 when I short the SCS connector with a paper clip. Code 35 is TCS FI Data Line Failure, which doesn't mean much to me. The TCS warning light has not come on since.

What I notice now is that with the ignition switch in position 2, sometimes the warning lights on the dash are dim, but if I turn the key half way to position 3, they come on brightly. Also when they warning lights are dim, I don't hear the main really click and the Malfunction Indicator Lamp (MIL) doesn't go out.

So I'm thinking this is an ignition switch problem and the error code 35 is related to poor connections in the switch.

Any thoughts anybody abut the diagnosis, before I take the ignition switch out? I found a very old post from Amo with a step-by-step for taking it out and it's explained at 23-72 in the manual. Amo initially recommended taking the switch apart and cleaning the terminals rather than replacing it .... but subsequently had problems with his refurbished switch. So looks like a new switch required!

Peter

Found this on NSXprime as well https://www.nsxprime.com/wiki/Ignition_Switch

[Kaz-kzukNA1]

As you mentioned, TCS error code was most likely triggered due to the repeated cycles of stalling/re-starting rapidly with sudden reset despite in IGSW P2-P3 phase.

From what you wrote, I even thought about the fuel pump relay or the fuel pressure related cause but since you can keep driving without any issues once the engine started, probably not the case.

With the healthy IGSW, not easy to diagnose using the following method but if the cause of your issue is the IGSW, it's in quite bad state so should be easy to test.

1. Setup the condition to carry out the following procedure safely.
For example, disengage the CL, keep the gear in neutral with parking brake engaged or in P range for AT.

2. Keep eye on the volt gauge.

3. Turn IGSW into P2 ON position.

4. Now you need the delicate touch.
Turn IGSW just a tiny bit towards P3 START position but without triggering the starter and release the IG key.
You may need some practice but you can also wiggle the IG key within minute angle from IGSW P2 towards P3 back and forth.

5. With the healthy IGSW, the volt gauge should stay at the same reading.

With the faulty IGSW with heavy contact fretting, you will see the volt gauge dropping randomly.

Very old video but should provide some idea on what I meant; https://youtu.be/BluBrNMSEjI

In the video, at the top side towards the right, you can see the reflection of my finger movement.

At the very beginning, I was not good at it and rotated the IG key too far that caused random reset between P2 and P3.
Or, I didn't turn the IG key far enough that the volt gauge stayed at the same reading.

Later, got used to on how to move the IG key that you can see the voltage drop even without making the warning lights dim.


If you decide to DIY, the old school pencil with the abrasive eraser at the top tip would become handy if you can still find one.

Or, get the fine sand paper or dremel tip and use your finger to re-surface the contact.


If replacing, OEM one is not that expensive at the current exchange rate but question mark on the delivery charge and the schedule from Japan as it's in the middle of long New Year holiday season.


There used to be few aftermarket options in the past but seems like just one option at the Rockauto???

I 'think' britlude has experience with the aftermarket one.

Although it's only held by tiny two screws behind the key cylinder, you need bit of flexible body to replace the IGSW.

If the big brown 250 connector is still held at the original position, you may find it really tight to separate it but manageable.


Kaz

[britlude]

There used to be few aftermarket options in the past but seems like just one option at the Rockauto???

I 'think' britlude has experience with the aftermarket one

Kaz

yup, i've used the rockauto option, seems exactly the same, plug and play swap in

but as Kaz says, can be a bit awkward to do if you haven't been in there before

[RedCarsGoFaster]

I have a RockAuto ignition switch fitted to my car - no issues with fitment other than the previously mentioned contortion required to get into the driver's footwell upside down. Big thumbs-up for service from RockAuto, too - all fees and delivery charge were included in the price, and it was delivered in only a couple of days. I've had longer waits from Amazon!

However, a word of warning if you happen to have one of the UK-market cars that were fitted with alarm/immobiliser systems within the UK dealer network. When I went to replace my ignition switch I found that the dealer-fit alarm system had been wired into the ignition switch harness, and so what should have been a simple replacement of the switch required the attention of an auto electrician.

[Old guy]

Good point on the aftermarket alarm systems. I had to replace the ignition switch on my 2000 because of badly done wiring modifications to the ignition switch. The aftermarket system had been removed before I took ownership of the car; but issues remained. The 'issues' should be self evident.



Since the car already had an alarm, starter interlock and being a 2000 an RFD immobilizer chip, I am presuming that a previous owner wanted keyless entry; but, not the OEM keyless retrofit system. I eliminated the ignition switch wiring bodge, put a new jacket on the harness and then pulled the switch apart to check the contacts.

.

After approximately 19 years of use the switch contacts were in remarkably good condition, just some wear-off of the surface plating; but, no gouging or pitting on the contact surface. I cleaned the contacts with some IPA and then applied some GB Ox-gard grease to the contacts. Oxgard is a grease that contains a suspension of zinc. The grease helps prevent oxidation of the contacts and the suspended zinc improves electrical conductivity (between contacts which have contact pressure). Deoxit D100L would also be an option for treating the contacts; but, it is significantly more expensive than Ox-gard and probably not as long term durable in a sliding contact application. Do not use dielectric / silicone grease for this application. Its an excellent insulator which is exactly the opposite of what you want.

One last point on installing the switch. Make sure that the switch contacts are in the '0' position when mounting the switch. On the rare occasion the switches have come packaged with the contacts rotated into one of the other positions. This will make it impossible to install the switch on to the back of the lock mechanism when the lock is in the '0' position.

As long as you are not built like a rugby person, replacement of the switch is not bad. Much, much easier than the dreaded upper clutch switch button / welcome to purgatory affair. A stubby screwdriver is a must and a small inspection mirror on a stock to get a visual of the switch without trying to get your head under there helps. I like to use a head-band mounted light to free both hands and I use a small blob of butyl putty to hold the screw on the end of the screwdriver when starting the screws during the reinstallation process.

[PeterW]

Thanks everybody for all the good advice.

Kaz's test method confirmed the switch problem. Good to know about the RockAuto option.

I took the switch out today and dismantled it. As with Old Guy's experience, the contacts were a bit cruddy with some minor wear. I gave it a good clean to get rid of the crud and polished the contacts with Brasso. I don't have any conductive grease and if I had would certainly have used it. But I figured that since there wasn't any evidence of Mr. Honda having thought grease was necessary, I'd do without. I'll buy some for next time!

Yes, I had to deal with Honda UK's after market immobiliser installation which had made a right mess of the switch harness and meant I had to cut wires to get it out. It's back in with bullet connectors now which will make it easier if I have to go back in there again.

So far the refurbishment seems to have worked, and it starts first turn of the key now .

Peter

P.S. If I have to do this job again I'm going to hire a limbo dancer to do its for me.

[Old guy]

I gave it a good clean to get rid of the crud and polished the contacts with Brasso. I don't have any conductive grease and if I had would certainly have used it. But I figured that since there wasn't any evidence of Mr. Honda having thought grease was necessary, I'd do without.

P.S. If I have to do this job again I'm going to hire a limbo dancer to do its for me.

Brasso would not have been in my repertoire of products; but, if it gets the contacts clean and doesn't leave any residue then no harm done. From new, the conductive grease probably has no merit. My switch was 19+ years and still switching fine if it were not for the bodged butt splices. I just figure that if the contacts have a little surface wear and the sliding contacts have lost a little of their spring pressure its a little insurance.

Replacing the ignition switch isn't bad. By comparison, you will need to charge up your expletives savings account if you ever have to re place the upper clutch switch stopper button .