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John C
07-09-2020, 11:02 AM
How do I check what is wrong with my SRS?
Please note I also had a lot of water in my boot, could this cause any contact problems?
After a short distance the ABS and TCS lights also come on, could they be connected?
This is my daily car and my MOT is due soon, so any help is appreciated.

NSXGB
07-09-2020, 11:48 AM
First step is to check for error codes.
Likely to be the fuse blown due to the capacitors in the SRS module leaking - common faults.
Year and spec of your NSX may help further.

John C
07-09-2020, 11:56 AM
Thank you for your prompt reply, it is a 1997 Auto.
How do I check the error codes for SRS?

Kaz-kzukNA1
07-09-2020, 02:20 PM
97 so it has passenger SRS as well.

SRS is not connected to the SCS blue 2pin connector and it also doesn't store any codes.
Thus, no code reading.

If you got the SRS warning light suddenly and didn't work inside the cabin recently, then as NSXGB mentioned, very likely to have blown the fuse.

Check #1 10A SRS fuse at the fuse panel located at the passenger footwell side wall inside the cabin.
You may find small yellow cover on top of the red 10A fuse.

If blown, most likely caused by capacitor leakage inside the SRS controller.
It's safety device so not recommending repairing.

Only done so with strict agreement with the owners in the past but never done the controller with the passenger SRS included.



For the ABS and TCS lights.....

Please confirm that your ABS is still the original classic one and not upgraded to the latest spec.

Please read the error code first.
http://www.nsxcb.co.uk/showthread.php?9229-How-to-read-the-error-code

After reading the code(s), reset the system (don't do this just before leaving for MOT although the SRS light will fail your MOT) and carry out another test driving session.

This is necessary as some of the codes could be stored long time ago and already fixed but the codes could be not reset yet.


The reset procedure is different if you have upgraded the ABS.

If your boot got lots of moisture and if the code includes the one for the Rear Right (RR) w/speed ALB sensor, addition to checking the resistance of RR sensor, you need to check the state of the Female terminal at the big grey 20+pin connector located at the left forward section of the boot behind the carpet.

I'll leave the detail for now as reading the code is the first.


Kaz

John C
07-09-2020, 06:33 PM
Thank you Kaz, sorry for the late reply but I had to go out. Strange that all the lights came on at the same time, that's why I thought they might be connected. The boot was actually flooded covering the tools, never happened before or since. Spent a long time drying it out. Found a bad connection on one of the brake bulbs. Car was slightly damaged when someone drove into me from the side. Now repaired by someone with a good reputation. Incident did not trigger the SRS light, this came on later.

Kaz-kzukNA1
08-09-2020, 10:54 AM
If there is an issue with the w/speed sensor, then it will trigger both the ABS and the TCS lights.
The raw sensor signal first enters the ABS controller, then the signal is filtered and level converted, then it will be passed onto the TCS controller.
Therefore, with the w/speed sensor failure, you would see first the ABS light and within 1sec or two, the TCS light will be triggered.

If you are saying that all three ABS/TCS/SRS lights were triggered simultaneously at the exactly the same timing or within a few seconds each other, then I agree, something suspicious and not true failure.

Not exactly the same but on UK spec NSX, if specific conditions were met, you could trigger the parking brake indicator (the big red circle at the gauge) by disconnecting the R-side taillight assy even when the parking brake was disengaged.
This is not the case with the JDM NSX.

Please read the error code first and then reset it.

Please clarify the spec of your ABS (classic or upgraded).

Also, bit more detail on exact timing on when the three lights were triggered.

By the way, did you jump start the car recently or what is the voltage reading in P2 ON position and while cranking?


I'm in the middle of suspension installation so may not be able to check the Forum for awhile.

Kaz

John C
08-09-2020, 04:44 PM
The car is UK spec. and yes you are right it has a passenger airbag.

As far as I am aware no modifications or upgrades have been done, and I have had the car for eleven years.

Yes the ABS light comes on first then shortly after the TCS light.

The warning lights started to come on when I put the car back on the road after it was repaired.

The SRS light does not go out when the engine starts.

The ABS light and TCS light go out when the engine starts, and come on again within half a mile.

My brake warning light is coming on again, (Including the hand brake) it appears that the passenger side bulb holder or wire might be faulty as it stops working when I re-install it.

The SRS 10A fuse appears to be OK, but I swapped it with the spare to make sure. The SRS light is still on.

I also checked the next fuse as the book stated that this was SRS 2, again this appeared to be OK.

I have not checked the error codes yet.

The car has never been jump started.

Voltage is 13 in P2 and 10 while cranking

John

britlude
08-09-2020, 04:49 PM
abs and tcs are more than likely to be wheel sensor related, as they go out at startup, but come on after the car has moved...... but the error code will confirm this....

Kaz-kzukNA1
09-09-2020, 10:53 AM
Battery seems to be healthy so no concern of power cycle reset during cranking causing CPU wakeup timing issue.

Could be wrong but with the open circuit w/speed sensor issue, the ABS light would trigger immediately without moving even on the classic ABS.
Mine is upgraded one.

If you need to drive the car even less than 1/2mile before triggering the light, then it could be the sensor signal noise issue that I experienced and not easily checked with the multimeter.

You are lucky that it triggered the ABS light though.
Different phenomenon but possibly the same cause as some of the NSX experienced no warning light yet your brake pedal would vibrate even when just applying tiny brake pressure at crawling speed.
Obviously, ABS should not operate like that and thus, should trigger the ABS light but the CPU power of the classic ABS can't analyse this type of failure.
Upgraded one can.

Reading error code will tell something.

I guess you are referring to the [BRAKE LAMP] warning at the bottom centre of the gauge as the 'brake warning light'.
Not sure why it would trigger the parking/hand brake big red circle light though.

If all brake light bulbs are fine, I would be worried about the gauge cluster capacitor leakage but since you mentioned that you are experiencing actual malfunction of the brake light, I would fix that first.

The parking brake indicator is also used as the brake fluid level warning. Check the master cyl cap but probably fine.
However, as your NSX is UK spec, would check the 20+ grey connector inside the boot behind the carpet.

If fuse #1 is fine, you could be lucky and the SRS controller may be OK for now.
It will help if you have electronics background as you don't want start testing the connection around the SRS system.

During the repair, any work carried out around the steering wheel, Driver/Passenger seatbelt retractor or passenger SRS unit area?

Hope it's just loose connector at the seatbelt pre-tensioner area or Drv/Pas SRS units, sensor, etc and not the steering wheel cable reel/clock spring.


Kaz

John C
09-09-2020, 12:45 PM
My electronics knowledge is virtually zero.

During normal braking I have not detected any vibration, however under heavy braking there is juddering, but I know that my discs need replacing, which I was going to have done when I put it in for servicing and MOT.

Yes the brake light I am referring to is bottom centre, below the boot open light.

Brake fluid level is OK just below Max.

Repair work involved removing drivers side rear wing and outer door skin, I suppose it could have upset the drivers side seatbelt, where do I look for the connector, is there a previous thread I can refer to?

Thank you for all your help

John

Kaz-kzukNA1
11-09-2020, 03:53 PM
Another super busy week and weekend so just a quick reply.
May not be able responding until next week.

Does your horn work?

Does your Cruise Control 'Set' and 'Resume' still operate properly?


Once you read the error code, please report back.



Strongly recommend not to touch any of the SRS connectors without knowing how it operates.
There is a super capacitor on the circuit board that will act as the power supply in case of loss of power during the accident.

This means that the SRS controller can still trigger the SRS inflator for several minutes even after disconnecting the battery.

You have been warned.



https://lh3.googleusercontent.com/B7majEpFkO2Kt7ryoyg7Xgj4qpGNrcRb3vmsP8BoIexrSS_LC6 buIvE9rvnexKBFuIyZ7DK1TBKygi4Y1gKGZ_xsVH8aUK9j0aeg Q7vJtkZ5DCg3xnGidPcKEAQpQCVmx63PWZBwRk2ip-9Yk4qL9eJntagZ-dQkkzQXxImXB8k2l0w-qKcknH2-6BGe2cV_PtFqAGsj4VmOyw7Sub5j62rgmGKoCKmBFtJ-PUNzkI519ZIWEOqY3lIN3kuENB6JuXIgSFClna5hm-Loqslva5WUu5YFE9-4SCf5JqokVDRmAeqLIP4QifaDt2LOUwIGvholNbcbAzhvVwYK4 LWALUhrvZax_6hQBaSjq4LXlU0vOeHpYB8rtAbz7mPQtp5l8OY 6GTe0iK5LVbc2rjEsvWB5s0ijYw2G966EBZiGuVZpw-L55PhhzeE_7vqD-pFt_AzhcKGrYnM8Vo0doNa3Nn_JzxXuvKiwFEN9vANe37-1naNrHKqxL-tFMM0F3DYfYyvq-ckx0kM361i9adQZ3C6NBOuSK4ZMI8PMq9RANh1wupl9cdH0wbP 2xtNdcvAUML-Qh7Y0roU-_KXJAa-3PiDHFkykS3omZsLfLgcXhIIKen8ViuAI9_-bgu61a_FnPW8H-zWAPU_dZ2hns0VPe-FrQvLuR-7TCEVFt_le243kKkha85sHK-dR7kLG2g=w1080-h810-no?authuser=0

https://lh3.googleusercontent.com/pw/ACtC-3cP0QEIs7hrYfE1lUFOJTGZ3_Nzj85ZplnbLcIzXuv1w5EFCkU IvTUoUkubvnsdT707osCFAPoMlSn2cihvqLrPIbfoUivp7t67b MTWXztH7oKx0L4Sv4n-unrWGTbk9RXD0VFi2VghTNAVYX9LO-5YYw=w1080-h684-no?authuser=0


If the centre pillar external panel (marked yellow) was removed during the repair, then the person had to remove the cabin side panel (marked #7).






https://lh3.googleusercontent.com/pw/ACtC-3ezZROFgkWC8AHMMbR-01UCL_graw56ifWScBBP_dK43qRlop5HnsVAaXmYnoD_KoRwnb f1FpVitoIS2sRzn0Oy7bv7Ew0Iti6jUYzbVKaTpuQXolUehLqr HLihe1e3wrfQ3ZExQcKU5O7KVS7PYHg7pw=w896-h1080-no?authuser=0
There is no need to touch the SRS seat belt tensioner for removing the above external panel but if you are just doing the visual inspection, then please refer to this.

Again, do not touch the connector and if you found that the connector was disconnected for some reason, DO NOT try re-connecting it.


Kaz

John C
19-09-2020, 01:57 PM
Apologises for the delay in replying.

The code readings were:

ABS 2 fast Parking brake applied while being driven?

TCS 2 slow Parking brake signal?

Also though not previously lit engine 4 slow?

I have fixed the passenger side brake bulb holder; this has had the following effect:-

rear brake light warning not on

Hand brake warning not on

ABS not on

TCS not on

Then reset (twice)

ABS no code

TCS still 2 slow

Engine still 4 slow

Do not know why I can not cancel them.

Re the SRS warning light. I am reluctant to work on this based on your warnings so I am going to study the manual carefully. My nearest Honda dealers are in Mansfield and Nottingham. The Mansfield dealership showed no interest in the vehicle and at the Nottingham one quite a few came out to look and ask questions, some saying that they had not seen one before.

I assume that either should be capable of checking the SRS system?

My local garage often has unusual vehicles in so I am thinking of taking it there.

Any opinions on what I should do?

Thank you again for all your help

John

NSXGB
19-09-2020, 02:27 PM
What is the state of your parking brake. Is it maybe one click up or adjusted too tight recently?

On the NSX there is a hidden feature that if you pull the parking brake up one notch and drive a short distance, it will disable your ABS and TCS, i believe for track purposes. I cannot remember the exact parameters but I'm sure Kaz will...
When I first read your symptoms, that is one of the first things I thought of. Hopefully an easy fix for you.