Code 5: Map Sensor
- Turn ignition off. Remove BACK UP fuse from underhood fuse/relay box for 10 seconds to reset ECU. Check ECU for fault codes. See RETRIEVING CODES
. If Code 5 is not present, problem is intermittent. Check all vacuum hoses and connections. Test drive vehicle and retest.
- If Code 5 is not present, turn ignition off. Connect hand-held vacuum pump to MAP sensor hose at throttle body. See Fig 1
. Apply vacuum. If vacuum holds, go to step 3). If vacuum does not hold, attach vacuum pump to MAP sensor. Apply vacuum. If vacuum does not hold, replace MAP sensor. If vacuum holds, check MAP sensor vacuum hose for cracks, splits and looseness. Repair as necessary.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
- Connect "T" fitting in vacuum hose between MAP sensor and throttle body. Start engine. If vacuum is not present, remove restriction from throttle body. If vacuum is present, turn ignition off. Connect ECU Test Harness (07LAJ-PT3010A
) between ECU and ECU connector. See Figure
. Turn ignition on. Measure voltage between test terminals D17 (+) and D21 (-).
- If voltage is not about 3 volts, replace MAP sensor. If voltage is about 3 volts, start engine, and allow it to idle. Recheck voltage between test terminals D17 and D21. If voltage is not 1.0 volt at idle, replace MAP sensor. If voltage is about 1.0 volt, substitute a known good ECU. If symptom/condition goes away, replace original ECU.