MAP sensor performance problem
The manifold pressure reading was electrically OK, but did not match what the engine was actually doing. This is a performance fault, not a wiring fault.
- Manufacturer
- Honda
- Platform
- PGM-FI (Keihin, Renesas M32R)
- Models
- CBR600RR
- Years
- 2003-2022
- Subsystem
- MAP sensor (performance)
- FI-light blink
- 2 short
- Hex
- 0x0201
Strongly inferred. Strongly inferred: the standard Honda meaning is well established, but exactly how this ECU handles it internally is inferred rather than fully confirmed.
What it means
Unlike 01-01 and 01-02, the sensor circuit here looks healthy: the value is in range, but it does not agree with the rest of the engine’s behaviour. The ECU flags this kind of implausible-but-in-range reading as a performance problem.
Conditions
Detection conditions
- The MAP reading is within its electrical limits, so the circuit codes do not apply,
- but it does not line up with the current running conditions.
Sets the fault when
- The mismatch persists (the exact comparison the ECU uses is not fully reconstructed).
Clears the fault when
- Fix the underlying problem, then clear the stored codes with a diagnostic tool or the manufacturer’s reset procedure. If the fault is still present, the code returns the next time the ECU detects it.
Parts involved
- Manifold absolute pressure (MAP) sensor
- Intake vacuum hose to the sensor
Symptoms & likely causes
Possible symptoms
- FI (check-engine) light on
- Fuelling that feels slightly off with no obviously dead sensor
Likely causes
- Vacuum hose to the MAP sensor leaking, blocked, or disconnected
- Intake air leak changing the real manifold pressure
- MAP sensor drifting out of calibration
Diagnostic guidance
The sensor circuit is usually intact here, so look first at the vacuum hose and for intake leaks rather than the sensor or its wiring.
How the ECU decides
A simplified view of the logic behind this code: a short C snippet with a plain-English summary. It shows the real decision the ECU makes without the low-level detail.
When the ECU confirms a fault, it saves the code and turns on the FI (check-engine) light. For a serious fault it also runs the engine on safe default values (limp-home) so you can still ride, with the light on.
// Once a fault is confirmed, remember it and warn the rider.
if (fault_confirmed) {
store_code(code); // kept until the codes are cleared
fi_light = ON;
if (fault_is_serious)
limp_home = ON; // safe defaults so you can ride home
}
Related codes
Questions about code 02-01
- What does Honda code 02-01 mean?
- The manifold pressure reading was electrically OK, but did not match what the engine was actually doing. This is a performance fault, not a wiring fault.
- Which motorcycles does code 02-01 apply to?
- It is documented here for the Honda CBR600RR (2003-2022). Other Honda models may use the same display code with a different meaning, so confirm against your model.
- Can I still ride with code 02-01?
- It depends on the fault. Code 02-01 relates to the MAP sensor (performance). If the bike runs poorly or a safety-related system is affected, avoid riding until it is checked. The FI light stays on until the fault is fixed and the codes are cleared.
- What should I check first for code 02-01?
- The sensor circuit is usually intact here, so look first at the vacuum hose and for intake leaks rather than the sensor or its wiring.
Sources
Every technical claim on this page traces to the research below. Source labels are sanitized; no local research paths are exposed.
- firmware
2005-2006 Honda CBR600RR ECU firmware
Factory PGM-FI firmware for the 2005-2006 CBR600RR. Primary source of truth.
- analysis
Firmware fault-code table extraction
Reads the list of codes the ECU can store directly out of each firmware.
- reference
HondaECU project (open-source Honda ECU tool)
Community reference mapping Honda PGM-FI codes to their meanings.
- analysis
CBR600RR ECU reverse-engineering analysis
Independent analysis of how the ECU detects, stores, and reports faults.