Relay Problem?

[NSXGB]

May have some kind of relay problem…
Went into the garage last night and heard a ticking noise from the car. Tracked it down to the ‘Sub Relay Box B’ on the passenger front inner wheel arch. Ignition was off, key in position 0 and the immobiliser on. There are 6 identical relays in this box and I tracked it down to the middle right, looking at the car. From the online service manual which is for a LHD car, I’m guessing this is either relay C213 or C214 (washer motor or ALB fail safe relay). Removed and reinstalled relay but it started clicking again. Removed relay, turned key to position 2, disabled immobiliser, all lights on dash came on (didn’t try to start the car). Turned off ignition, replaced relay – no clicking. Went to start the car this morning, battery totally dead. Guess it started clicking again later on!

That is the sum of my investigation so far. Will charge battery tonight and continue investigations tomorrow when charged.

Anyone had this issue before?

If I have the correct relays identified I will try to use the washer motor (very seldom used), drive the car to see if there are any warning lights and trigger the ABS…. Hopefully someone had had this issue before and can shed some light prior to my impending head scratching.

[Kaz-kzukNA1]

Hi, NSXGB.

Could you take a photo of the relay box to show the exact position of the relay in question???
There were several reports of stuck closed, burnt relay contact, etc on these relays (speaker relay, etc) so no surprise.
If you have upgraded the ABS, depending on the ABS upgrade loom you are using, some of the relays from the classic ABS are no longer in use.


Kaz

[NSXGB]

Hi, NSXGB.

Could you take a photo of the relay box to show the exact position of the relay in question???
There were several reports of stuck closed, burnt relay contact, etc on these relays (speaker relay, etc) so no surprise.
If you have upgraded the ABS, depending on the ABS upgrade loom you are using, some of the relays from the classic ABS are no longer in use.


Kaz

Thanks Kaz.

Will get a photo tonight but in the meantime I have done a quick sketch which may answer the question.
12623
The relay box is the one on the passenger side front inner wing. From memory there are 6 smaller black relays the same and about 4 larger ones closer to the front of the car.
Shown on page 23-23 of the 1991 Acura Service Manual.

[Kaz-kzukNA1]

https://lh3.googleusercontent.com/wvcL1aZgHXqzmj-bMCpqWA4OHLl3DygmkYLemFuhrsKpyuzYPfqBsTiEG82GB1pwE LSXTnzPobqghKxmbzqbbJlaoJymaGcff-Xz94MHjnYlSZ5PuJHwUi-fcSzZMNth_wwftVvVOELItA0YU7RdZMl1-j2ddywuIB5LS5sWOz4OwTQhV3Wa5bK0PzqGW0JG3EXcz0xhpJY YnaERBkXgMa8JqdpSYqs2nUMwc28eK7UALPIjxM6qK2vxMMFud liobWUPIRjIjDoq45cvojnSY3bZJE2iiYd7ufS6NiP5OqvpFW7 2ThCSa1cNNHWRU2IGSiyvHqcG-fGZpaS3c9P70S1bVUt0k0vwQMrIPi2reOxevb4D5_JWZi5djHa hAzOhrMNTUR_SO-fNP3UDCEOqQgfaKf1tBv9U2RIms-430myYZHKYRGwWSe_I26-VgSv6FM5m3y7odEEdF83RMs7uMoX-wmimpFoVMZ6KFPsnB_8340RO6ukjbWE8ElIr67bHjuYJ5fo8A1 ZY1SSVDvfP8oCSttxaTxenslrEjyTnc53ijYmR40i88HPgmmyM Q8gnBN9l2UFwfgycmhdGm0nUHI50fCzQwcdS=w1080-h810-no

Guess what, welcome to the sticky speaker relay club.


This photo is only for the RHD model until around 96 model or earlier (but I could be wrong).

The actual relay being used may look different from this photo (my JDM 94 model uses different relay shape but exactly the same relay function and layout) and on later year model, the relay function is completely different so please be careful.


If it's the speaker relay, the switched terminal is sourced from +B so always at battery power and the coil side is controlled by the OEM audio head unit or aftermarket one so if it gets sticky, it will always power up your speaker AMP.

Or, there could be something activating the coil side and switching the Relay ON but the coil side is controlled by Switched +B so unless the head unit is powered up (even without the IG key....), it is very unlikely to be able to activate this relay.

Just borrow one of the nearby relay that has the same parts # on the relay body and see whether it will stop the ticking noise.


Kaz

[NSXGB]

That's the one.
Battery 80% charged, relay not clicking at the moment. Get a click from it when I turn the key to position 2, which from what you mention is expected. Tried another relay in its place with the same result.
Relay is a Mitsuba RC-2225 for reference - £41 from Honda.

[WhyOne?]

Nothing by way of technical assistance I can offer, but if it would help to borrow any parts from my car for diagnostic purposes, please don't hesitate to ask.

When I had the problem with my alternator, I had all manner of clicking going on, but this seemed to be from boxes on the bulkhead behind the seats.

[NSXGB]

Thank you for the offer Ian, I should be OK though as I think I have some spares....somewhere...

Left the relay in last night and no further clicking or dead battery this morning.

[Kaz-kzukNA1]

From memory, I think you have upgraded the ABS to the latest spec.
If that is the case, you can use the relay from ABS Front F/S or ABS Rear F/S in the above photo.
Same NO type RC-2225 used for them.
They are not in use by the upgraded ABS and just additional weight.
They used to control the low side of the ABS solenoids through the orange connectors in front of the ABS modulator but if you have upgraded the ABS, these orange connectors are no longer in use.

If you don’t like leaving the space blank inside the relay box, just mark the dead relay and use it as a blanking plug.


By the way, if you are using the aftermarket ICE with the external AMP unit, please check the spec of the switched +B from the aftermarket head unit.
In order to prevent the ‘pop’ noise from the speaker on powering up the head unit, normally it won’t wake up the AMP until the head unit requests to do so. This depends on how you ran the power line to the AMP as well, if you are using the external AMP unit. Just curious to know that your relay engages in P2 even when your head unit is powered off???

With OEM system, the switched +B is used for the power ANT as well.
This is the reason why you always see your antenna going up when you power up the OEM head unit even when you are in the CD mode.



Kaz

[NSXGB]

From memory, I think you have upgraded the ABS to the latest spec.
If that is the case, you can use the relay from ABS Front F/S or ABS Rear F/S in the above photo.
Same NO type RC-2225 used for them.
They are not in use by the upgraded ABS and just additional weight.
They used to control the low side of the ABS solenoids through the orange connectors in front of the ABS modulator but if you have upgraded the ABS, these orange connectors are no longer in use.

If you don’t like leaving the space blank inside the relay box, just mark the dead relay and use it as a blanking plug.


By the way, if you are using the aftermarket ICE with the external AMP unit, please check the spec of the switched +B from the aftermarket head unit.
In order to prevent the ‘pop’ noise from the speaker on powering up the head unit, normally it won’t wake up the AMP until the head unit requests to do so. This depends on how you ran the power line to the AMP as well, if you are using the external AMP unit. Just curious to know that your relay engages in P2 even when your head unit is powered off???

With OEM system, the switched +B is used for the power ANT as well.
This is the reason why you always see your antenna going up when you power up the OEM head unit even when you are in the CD mode.



Kaz

Great, thanks Kaz.
Yes, I have the upgraded ABS.
I have an aftermarket double DIN head unit, running the OE Bose amps. I don't get a pop from the speakers sinceI installed a pair of HPF's.
My head unit is always on which I guess is why the relay engages every time...

[NSXGB]

Is there an uprated version of this relay available?

[Kaz-kzukNA1]

Mitsuba RC-2225 is a power relay and even used for driving R & L fog lights (55W x 2) continuously with 15A fuse so it can easily handle 15A with safety margin on top.
Denso one is 056700-7250 (39794-SE0-003) and it's the same one used for driving the ABS pump motor with 40A fuse.
As you have upgraded ABS and if you are using KSP or T3TEC loom, you no longer need this Denso relay for the ABS pump motor inside the pentagonal Main Relay box under the bonnet so just use it in place of the Speaker AMP relay.

You can use the Denso relay instead of Mitsuba one as both relays have the same foot print and interchangeable but Mitsuba relay is widely used on many production cars so unless you are exceeding the OEM design spec, not sure you need upgrading.....

The only downside of using Denso one is that because of its shape and height, it's almost impossible to remove it without first removing the relay sitting next to it.
Mitsuba one is so much easier to handle.


Kaz

[NSXGB]

My reasoning was that if the relay was 'upgraded' to a higher spec (even though it has sufficient safety factor already) it would maybe extend the life over all? If it can handle 40A though, that should be much much more than my head unit should ever require.
I have repositioned one of the ABS relays already as you suggested. They are do take a bit of a wiggle to remove!