2002 S80 2.9 NA SOS Beep Mystery

htimsenyawed · Post by **htimsenyawed** » 25 Jan 2024, 08:40

Curious issue I have here. I noticed that my tail lights, and tail lights only, were pulsing on for one second and off for one second. This, of course, depleted the battery.

However, I wanted to see if there was an issue that was present on the dash without starting the vehicle - so I put my key in the ignition and turned the key to the first position. When placed in the first position, I received the SOS code beep - high pitch, twice in succession. (... --- ... / ... --- ...) and then the battery finally died out after the SOS beep finished playing the second time.

I've called two Volvo service departments, neither of them have ever heard of these SOS beeps. I called Volvo Cars America and there is no SOS beep in any of their documentation. I don't have international calling, or I'd contact Volvo Cars Sweden (I tried, it doesn't work).

Has anyone here ever experienced, or at least heard of, an SOS beep from the S80?

JBaldy · Post by **JBaldy** » 26 Jan 2024, 06:15

I don't know the answer but that is interesting. So, the taillights were pulsating when the car was just sitting there not running and without the lights on?

htimsenyawed · Post by **htimsenyawed** » 26 Jan 2024, 07:13

JBaldy wrote: ↑26 Jan 2024, 06:15 I don't know the answer but that is interesting. So, the taillights were pulsating when the car was just sitting there not running and without the lights on?

Yeah, I stepped outside, and it was one second on, one second off. Tail lights only, no other lights.

Post by **volvolugnut** » 26 Jan 2024, 07:54

Sounds like this is the emergency flashers and the beep is the relay to drive them. Perhaps with some other cross wiring issues. Has the emergency flasher button been accidentally pressed?
volvolugnut

htimsenyawed · Post by **htimsenyawed** » 26 Jan 2024, 08:06

volvolugnut wrote: ↑26 Jan 2024, 07:54 Sounds like this is the emergency flashers and the beep is the relay to drive them. Perhaps with some other cross wiring issues. Has the emergency flasher button been accidentally pressed?
volvolugnut

To my knowledge, no. Whenever I put the key in the first position to check for any errors is when I received the SOS beep - which isn't documented as a feature this car has anywhere online or in Volvo's documentation.

I have the battery pulled and on a charger/maintainer until I determine if this is a parasitic draw. My thought process is leading me towards the alarm module - I never lock the doors because it is known bad and would drain the battery if I activated it. I'm curious if, after I get to the module and disconnect it, if this will resolve my issues.

JBaldy · Post by **JBaldy** » 26 Jan 2024, 09:28

[/quote]
I have the battery pulled and on a charger/maintainer until I determine if this is a parasitic draw. My thought process is leading me towards the alarm module - I never lock the doors because it is known bad and would drain the battery if I activated it. I'm curious if, after I get to the module and disconnect it, if this will resolve my issues.
[/quote]

If you are referring to the siren module in the front right wheel well you should be getting an error message about it. If its like my 2000, you should be able to pull the 5amp fuse on the drivers side of the dash to take it offline.

htimsenyawed · Post by **htimsenyawed** » 26 Jan 2024, 09:33

JBaldy wrote: ↑26 Jan 2024, 09:28 If you are referring to the siren module in the front right wheel well you should be getting an error message about it. If it’s like my 2000, you should be able to pull the 5amp fuse on the drivers side of the dash to take it offline.

No error message unless I arm it, but I don’t do that. Is the fuse tied in with any other system? Like an ignition immobilizer or anything?

JBaldy · Post by **JBaldy** » 26 Jan 2024, 11:35

The 5 amp fuse I'm referring to is for the Siren module only and is labeled as such. This is the module that has its own internal battery that can take a dump on the PCB rendering the whole thing useless. Would have to spend a couple hundred to replace it or if you are lucky and the board is salvageable an improvised replacement battery could fix it. Lots of youtube videos about that. With the fuse pulled I do get a Siren error message.

htimsenyawed · Post by **htimsenyawed** » 26 Jan 2024, 11:37

JBaldy wrote: ↑26 Jan 2024, 11:35 The 5 amp fuse I'm referring to is for the Siren module only and is labeled as such. This is the module that has its own internal battery that can take a dump on the PCB rendering the whole thing useless. Would have to spend a couple hundred to replace it or if you are lucky and the board is salvageable an improvised replacement battery could fix it. Lots of youtube videos about that. With the fuse pulled I do get a Siren error message.

Fair enough. My siren is known bad, that's why I don't lock the doors because it will drain the battery. It seems that a severely bad/damaged siren module can cause parasitic draw.

htimsenyawed · Post by **htimsenyawed** » 26 Jan 2024, 11:57

JBaldy wrote: ↑26 Jan 2024, 11:35 The 5 amp fuse I'm referring to is for the Siren module only and is labeled as such. This is the module that has its own internal battery that can take a dump on the PCB rendering the whole thing useless. Would have to spend a couple hundred to replace it or if you are lucky and the board is salvageable an improvised replacement battery could fix it. Lots of youtube videos about that. With the fuse pulled I do get a Siren error message.

So, I have an issue that's beyond the fuse - because the fuse isn't installed for the alarm module.