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Fuel pump not priming , wondering where the fuel pump relay is located on 2021 model cbr650r

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
Went to start the cbr650r the other day and to my suprise no hum from the fuel pump. Everything else works lights indicators , horn , bike turns over but doesn't fire ,
I'm trying to locate where exactly the relay is for the fuel pump , with several Google searches and some saying under the fuel tank which I have lifted only to find the flasher relay next to the abs assembly and no other relays it only leaves the three that are in the main fuse box under the seat swapped them all around and still no humming or priming from the fuel pump any ideas ?
 

miweber929

2014
CBR650F
650 Alumnus
Staff
Feb 13, 2015
Woodbury, MN
Riding Since
1975
Went to start the cbr650r the other day and to my suprise no hum from the fuel pump. Everything else works lights indicators , horn , bike turns over but doesn't fire ,
I'm trying to locate where exactly the relay is for the fuel pump , with several Google searches and some saying under the fuel tank which I have lifted only to find the flasher relay next to the abs assembly and no other relays it only leaves the three that are in the main fuse box under the seat swapped them all around and still no humming or priming from the fuel pump any ideas ?
The link to the service manual is in the resources section of the site.

If everything else works I’d start looking at things that stop it from starting: clutch pin switch, kill switch, kickstand switch, neutral indicator are a few people have had issues with.

Had you done anything to bike beforehand, no matter how trivial it seems? Any symptoms leading up to it?
 

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
Other that being caught in the rain on a ride home from work no
 

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
Have ruled out clutch switch neutral and side stand switch as well as bank sensor
 

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
Have had a look lifted the tray that's separates the tub that's meant to house them and the abs module. Only sort of relay there is the 8 pin flasher relay and nothing else that's why I'm stumped as to where else to look , there's 3 x 4pin relays in the main fuse box under the seat any ideas as to what they are ?
 

Brammers

2014
CBR650F ABS
Staff
May 30, 2014
Hampshire, England
Riding Since
1993
Wiring diagram in the back of the service manual will be the document to read for that info.

I'm not near my copy at the moment.

J
 

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
Just had a look in both the owners manual and service booklet and I don't seem to have any sort of wiring diagram
 

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
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Okay so upon reading the manual it says that one of these 3 relays is the fuel pump relay , any one knows for certain which of the 3 it is before I pull the the tub out to have a look at the wire colours underneath
 

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
Yes but it's just says relay , doesn't state what circuit they're for
 

Brammers

2014
CBR650F ABS
Staff
May 30, 2014
Hampshire, England
Riding Since
1993
They're all the same part. Look at the numbers.

Just swap them until you locate the dead one.

I expect the other two are for indicators and fan.

J
 

Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
They're all the same part. Look at the numbers.

Just swap them until you locate the dead one.

I expect the other two are for indicators and fan.

J
So just back from the lock up with the bike and have found that all relays click when plugged into the main relay connection, however when all relays are plugged into the fuel and fan s connections no click at all , does this mean a possible short circuit on those two plugs in the fuse box
 
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Calcbr650

2021
CBR650R
Feb 17, 2025
Riding Since
2018
So multi metre cam out tonight the relays are recieving power but no input to the power pins but aren't receiving any volts or signal from the ECU pins
 

Brammers

2014
CBR650F ABS
Staff
May 30, 2014
Hampshire, England
Riding Since
1993
Check all connectors / wiring then. If that's all OK then it's going to starting to look like a broken ECU.

ECUs are usually pretty reliable though ... so more likely a broken wire / bad connector.

J
 
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