Code 4, 9, 54 Or 59: Crank/CYL Sensor
WARNING: This page is about a different car, the 1992 Acura Legend. However, it is still accessible from the selected car via links, so may be relevant.
- Turn ignition off. Remove fuse No. 15 (ACG) in underdash fuse box for 10 seconds to reset ECU. Start engine, and connect jumper wire to self-diagnostic connector. Observe CHECK ENGINE light. If Code 4, 9, 54 or 59 is not present, problem is intermittent. Check for poor and loose connections at CRANK/CYL sensor connector and ECU connector. Test drive vehicle and retest.
- If Code 4, 9, 54 or 59 is present, turn ignition off. Disconnect 8-wire connector from CRANK/CYL sensor. Check wiring harness and terminals. See Fig 1
. Check resistance of each sensor at indicated terminals. See INPUT SIGNAL & RESISTANCE TEST TERMINALS
table. If resistance is not 650-900 ohms, replace CRANK/CYL sensor. If resistance is 650-900 ohms, go to step 3).INPUT SIGNAL & RESISTANCE TEST TERMINALS
Sensor Code ECU Terminals Sensor Terminals CRANK 1 4 B15 A B16 B CRANK 2 54 B14 C B13 D CYL 1 9 B12 G B11 H CYL 2 59 B9 E B10 F - Check continuity to body ground on each terminal. If continuity exists, replace CRANK/CYL sensor. If continuity does not exist, reconnect 8-pin connector. Connect ECU Test Harness (07LAJ-PT3010A ) to ECU connector, leaving ECU disconnected. Check resistance between ECU terminals. See INPUT SIGNAL & RESISTANCE TEST TERMINALS table.
- If resistance is not 650-900 ohms, repair open in faulty circuit. If resistance is 650-900 ohms, check for continuity to body ground on terminals B9, B11, B13 and B15. If continuity exists on any terminal, repair short circuit. If continuity does not exist, substitute a known good ECU. If symptom/condition goes away, replace original ECU.