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SRS code 51-21 SRS control unit internal failure

623 Views 7 Replies 3 Participants Last post by  stezie
Hi all,

Wondering if anyone has come across this code before to help trouble shoot this error? Is my SRS module dead? I have the car test today at 3 too.. 😟
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Your error code 51-21 is not listed or identified as an potential problem or failure of the internal SRS unit or Supplemental Restraint System Unit.
I would suggest you seek-out a garage that has a more expensive SRS diagnostic tool to pinpoint your problem.
FYI - Below I have listed the current know 51-** error codes.
51-2, 51-4, 52-8, 52-9, 52-A, 52-B, 52-C, 52-D, 52-E, 52-F, 52-1, 53-2, 53-3,53-4, 54-1, 54-2, 54-3, 54-4, 54-6, 54-7, 55-1, 55-2, 55-3 & 55-4
NOTE: Having stated the above this does not rule-out the fact that you may indeed have a problem with Supplemental Restraint System Unit.
Your error code 51-21 is not listed or identified as an potential problem or failure of the internal SRS unit or Supplemental Restraint System Unit.
I would suggest you seek-out a garage that has a more expensive SRS diagnostic tool to pinpoint your problem.
FYI - Below I have listed the current know 51-** error codes.
51-2, 51-4, 52-8, 52-9, 52-A, 52-B, 52-C, 52-D, 52-E, 52-F, 52-1, 53-2, 53-3,53-4, 54-1, 54-2, 54-3, 54-4, 54-6, 54-7, 55-1, 55-2, 55-3 & 55-4
NOTE: Having stated the above this does not rule-out the fact that you may indeed have a problem with Supplemental Restraint System Unit.
Currently using v2020 of auto com. I have a HDS also, but I think that is broken as it keeps giving a red light on connecting after pressing blue button.

Recommendations on software to use?
Computer Personal computer Netbook Output device Peripheral
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Cannot help you with your HDS tool.

To many scanners / diagnostic tools on the market too choose just one, but have a look at these guys they have lots of equipment to suit everybody’s pocket.
LINK
Does anyone know if the Aigbag module is coded to the VIN on mk9? If I get an identical part number module should it work without coding?
H Stezie...did you solve the problem? what is the cause of this error? i have the same error in honda civic mk9 2014
I sent the SRS module to a specialist and they said the circuit board was damaged, and un repairable. replacement was only option.

my local Honda dealer said that the part number was "unavailable" so they couldn't order a new one for me.

Only solution is to take the part number from the module and try find one in a breakers/ eBay. It took me weeks to find one.

Some breakers may have the module you need, but wont sell it if it has crash data on it. you could persuade them to sell you one and have another company remove the crash data.
I sent the SRS module to a specialist and they said the circuit board was damaged, and un repairable. replacement was only option.

my local Honda dealer said that the part number was "unavailable" so they couldn't order a new one for me.

Only solution is to take the part number from the module and try find one in a breakers/ eBay. It took me weeks to find one.

Some breakers may have the module you need, but wont sell it if it has crash data on it. you could persuade them to sell you one and have another company remove the crash data.
When I did find a replacement module it plugged in and cleared error code light on dash right away. it didnt need coded to a VIN, or codes erased etc.
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