SRS indicator comes on periodically; but, no SRS DTC(s) set
If the SRS indicator comes on periodically and there are no SRS DTC(s) that are set, the alternator charge voltage should be checked the instant the indicator comes on. A bad voltage regulator can let the system voltage exceed the allowable voltage threshold of the SRS control unit.

SRS indicator comes on with SRS DTC(s) set
If the SRS indicator comes on, the car should be scanned for DTC(s).
For DTC such as 53-2X (53-20 to 53-29, 53-2A to 53-2F), 53-3X (53-30 to 53-39, 53-3A to 53-3F), 53-4X (53-40 to 53-49, 53-4A to 53-4F): Internal Failure of SRS Unit, you would erase the DTC memory.
1. Then turn ignition to ON and check that the SRS indicator comes on for 6 seconds and then goes off. If the SRS indicator stays on and DTC 53-2X, 53-3X, or 53-4X is indicated, the SRS unit should probably be replaced.
2. If the SRS indicator comes on for 6 seconds and then goes off, the issue would be an intermittent failure, as it checks okay now.

To troubleshoot an intermittent failure, you would erase the DTC memory. Set the parking brake, start the engine and let it idle. The SRS indicator should come on for 6 seconds and then go off.
You would then do things like:
· shake the wire harness and connectors
· take a test drive (quick acceleration, quick braking, cornering)
· turn the steering wheel full left and full right and hold it there for 5 to 10 seconds

If there was a malfunction, but it doesn’t recur, it will be stored in memory as an intermittent failure and the SRS indicator may or may not come on depending on the malfunction detected. If the problem recurs, the SRS indicator will come on.

A scanner capable of reading Honda SRS/ABS trouble codes would a more efficient and accurate way to check for intermittent DTC(s) even if the SRS indicator is not on yet.

 

Thanks for this info.

So if I'm understanding this correctly, then my situation would be considered an "intermittent failure" and would NOT fall into the category where the SRS computer needs to be replaced? The bolded part is what happens in my situation.

I've cleared the SRS DTCs via the MES connector and the SRS light does not stay on after the codes are cleared. However, it will come on during the next drive, and then when the car is turned off and turned back on, it will be off again until some point into the drive.

By the way, I ordered a scanner that can read Honda SRS codes, so I will see if it matches the 5-3 code I've been getting with the paper clip method.

Regarding the battery, I recently replaced the 5 year old Honda battery with a new one from Costco, and cleaned the battery terminals before putting in the new battery. The car has never had any problems with slow cranking or not starting. I haven't seen any other electronics problems, like the lights flickering or anything like that. So it would seem to me that the alternator/battery are doing okay.

 

It could be an issue with the wiring or harness connectors (there are two connectors for an '03) to the SRS unit, etc.; or a faulty SRS unit if the same DTC keeps recurring intermittently.

 

I will double check this once I get the scanner, but I've tried reading the codes several times with the paperclip method and the only code I've seen is the 5-3 (Internal failure of SRS) code. 5 long flashes and 3 rapid flashes of the airbag light when pins 4 and 9 on the OBDII connector are shorted. Prior to getting the seat belt components replaced, I was getting 6-1 and 5-3, but the 6-1 is now gone after resetting the DTCs.


Have you ever seen a case of a faulty SRS unit causing intermittent SRS DTCs? My situation is a little frustrating because about 99% of the forum posts about SRS lights are about the seat belt buckle/tensioner, and I've had both of those replaced recently.


The dealership seems to think it's a wiring harness issue (they want to charge several hundred $ just to look at the wires, with no guarantee of a diagnosis or fix). To me at least, the problem seems to happen a little too consistently to be caused by a loose connector somewhere. When I make a tight turn or go over a bump, the SRS light doesn't come on, and those are things that would be likely to bump a loose connector out of place and make it lose signal. The light normally comes on ~15 minutes into a trip, usually after braking on a downhill segment of road, or when I'm just idling after coming to a stop. On some trips, the light is totally fine and doesn't come on, so I've been unable to find a consistent way to make the SRS light come on.

I checked under the seats and all the connectors seem to be tight. I also took out the center console storage box (under the CD changer) and looked at the connections in there. There is a little bit of wiggle in the 2 big connectors going into the SRS computer, but they seem to be locked into place pretty decently with the plastic latches. Here's a picture of it:




By the way, if the problem was due to a loose connector, would I be getting a different code from "Internal failure of SRS"? For example, if the connector to the buckle was loose, that should lead to a seat belt buckle code (6-1 on an 03 Accord), right?

 

Finding an intermittent, and yours has a very long period, is practically impossible. You don't even know which circuit to monitor for fault.

I looked on car-part.com and found SRS computers (computer not engine) for as little as $50. I would try that before spending money on a new wiring harness.

There are apparently some differences in SRS computer for coupes, sedans, country of origin, trim level, etc. So if you go for a replacement, be careful to match your vehicle precisely.

good luck

 

FWIW: This may not have anything to do with your problem; but, the following may give a little more insight into the SRS unit.

Honda had a SRS recall for the 2003-04 Odyssey due to electrical noise (interference) generated by the vehicle which may inadvertently cause the front airbags to deploy.

What was found from an investigation was that SRS unit's ASIC chip can degrade over time. Analysis determined that, when actuated, the electric power door lock circuitry on both the Odyssey and MDX produces high levels of electrical noise. The electrical noise, which is transmitted to the SRS ECU via harnessing, may cause damage to the ASIC chip. Cumulative damage to the ASIC chip results in an inadvertent deployment event.

Defect Investigations Results | Safercar.gov | NHTSA

Honda replaced the SRS unit's subharness with a new one that included a noise suppressor.
Honda TSB 13-088

The 2003-2004 Accord and a few other Honda/Acura models uses the same ASIC chip. But, Honda identified differences in electrical system architecture and electrical noise emission levels between the non-recalled and recalled products.

 

This is the DTC that is being stored in memory:



Honda's troubleshooting steps for this DTC state:

1) Erase the DTC memory
2) Turn ignition to ON (II), and check that the SRS indicator comes on for about 6 seconds and then goes off.

If the SRS indicator stays on --> Replace SRS unit
If the SRS indicator goes off --> Intermittent failure, system is OK at this time.

On mine, the light does go off after ~6 seconds, but comes back on during the next drive. So would this still be a symptom of a bad SRS unit? Just want to be relatively sure that the SRS unit is actually causing the problem before I shell out the money for a new SRS computer.

 

Didn't want to bump a thread from nearly 10 years ago, but I figured I should post an update since I've gotten several PMs about this issue.

I no longer have the car, but I did end up replacing the SRS computer around 2014/2015 and it fixed the problem completely. Cost about $300 in parts/shipping, but well worth it.