How to reading Diagnostic Trouble Codes (DTC) without special tools or software

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Been asked this one several times now, maybe Admin will make a sticky of it!

You don't need any special tools or software to read the codes, its mostly in the workshop manuals

MKI (SC58) Section 6 FUEL SYSTEM (PGM-FI), page 13 scroll down to "Reading DTC with the MIL" where it describes how to read the codes using the Honda SCS (Service Check Short) connector 070PZ-ZY30100, pattern connectors can be had off eBay. The codes are listed on page 16.
MKII (SC64) Section 5 FUEL SYSTEM (PGM-FI) pages 16 to 17, the DTC index is on page 19

Links

MKI (SC58) CBF 1000-A Workshop Manual FUEL SYSTEM PGM-FI
MKII (SC64) CBF 1000F Workshop Manual

eBay pattern SCS Connector

Or its possible to read the Diagnostic Trouble Codes (DTC) by the PGM-FI Engine Check Lamp (MIL) with a jumper wire or paper clip...

Reading Diagnostic Trouble Codes (DTC) by the PGM-FI Engine Check Lamp

A.   Current Codes - If the PGM-FI engine check lamp is on with the engine idling engage neutral gear and put the side stand down. The PGM-FI lamp will start flashing any active codes.

B.   Stored Codes - If the engine PGM-FI check lamp is off you can read any stored codes as follows

Remove the seats. Locate the Data Link Connector (DLC) it’s a square 4P red socket that can be found below the riders seat in a clear plastic sheath just in front of the main fuse box. It is closed off by a dummy cover, depress the tab to remove it and you’ll see four female terminals, the wires are coloured

•   Black/white (12V switched live)
•   Orange/white (diagnostic)
•   Brown (Service Check Short)
•   Green (Chassis ground)

With the ignition switched off short the brown and green wire terminals with a jumper wire or paperclip.
Turn the ignition ON and watch the PGM-FI engine check lamp. If there are no codes stored the lamp will come on and stay on, if there are any stored codes the lamp will flash the DTC main code, the sub code cannot be flashed by the lamp.

The PGM-FI engine check lamp has two types of flash, a long 1.3 second flash and short half second flash. One long flash equals ten short flashes. For example, when two long flashes are followed by three short flashes, the DTC is 23 (two long flashes equals 20 plus the three short flashes equals 23). When the Engine Control Module (ECM) stores more than one DTC the lamp will flash the lowest code first. When finished turn the ignition switch off, remove the jumper wire or paper clip and replace the dummy connector.

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You can clear any stored DTC’s in a similar way.

With the ignition switched off short the DLC brown and green wire terminals with a jumper wire or paperclip.
Turn the ignition on and remove the jumper wire. The PGM-FI engine check lamp will light for approximately 5 seconds, while the lamp lights short the brown and green wires again.
When the lamp starts flashing the stored DTC’s have been erased, turn the ignition switch off, remove the jumper wire or paperclip and replace the dummy connector.

Diagnostic Trouble Code Index

1.    Manifold Absolute Pressure (MAP) sensor or its circuit malfunction
2.    MAP sensor hose disconnection or poor connection
7.    Engine Coolant Temperature (ECT) sensor or its circuit malfunction.
8.    Throttle Position (TP) sensor or its circuit malfunction
9.    Intake Air Temperature (IAT) sensor or its circuit malfunction
11.    Vehicle Speed (VS) sensor or its circuit malfunction
12.    No. 1 Injector or its circuit malfunction
13.    No. 2 Injector or its circuit malfunction
14.    No. 3 Injector or its circuit malfunction
15.    No. 4 Injector or its circuit malfunction
21.    O2 sensor or its circuit malfunction
23.    O2 sensor heater or its circuit malfunction
29.    Idle Air Control Valve (IACV) or its circuit malfunction

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Note the location of the Data Link Connector on the later SC64 (MkII) face lift model is under the fuel tank.