CODE 20 - ELECTRIC LOAD DETECTOR
1. Turn ignition off. Remove hazard fuse in main fuse panel for 10 seconds to reset ECU. Start engine and observe "CHECK ENGINE" light. If light is off, problem is intermittent. Test drive and check again.
2. If light is on, turn ignition off. Open lid of main fuse panel in engine compartment. Disconnect 3-wire electrical load detector. Turn ignition on. Measure voltage between Black/Yellow (pos.) And Black (neg.) Wire terminals of harness. If battery voltage is present, go to step 4).
3. If battery voltage is not present, measure voltage between Black/Yellow wire and ground. If battery voltage is now present, repair open in Black wire between connector and ground. If battery voltage is not present, repair open Black/Yellow wire between No. 14 fuse and connector.
4. Turn ignition off. Connect ECU test harness between ECU and ECU connector. Disconnect connector "B" from ECU side only. Connect Green/Red terminal of load detector harness connector to ground. Check for continuity between ECU terminal B19 and ground. If continuity does not exist, repair open Green/Red wire between ECU connector terminal B19 and load detector connector.
5. Reconnect connector "B" to ECU. Turn ignition on. Measure voltage between Green/Red (pos.) And Black (neg.) Terminals of load detector harness. If 4.5-5 volts is present, go to step 7). If 4.5-5 volts is not present, disconnect "B" connector from main wiring harness, not ECU. Measure voltage between terminals B19 (pos.) And A18 (neg.)
6. If voltage is now 4.5-5 volts, repair short in Green/Red wire between ECU terminal B19 and load detector connector. If voltage is not 4.5-5 volts, substitute a known good ECU. If correct voltage is now available, replace original ECU.
7. Reconnect load detector connector. Measure voltage between terminals B19 (pos.) And A18 (neg.) Under the following conditions.
I) Headlight switch in first position - Voltage should be 2.5-3.5 volts.
Ii) Headlight switch in second position - Voltage should be 1.5-2.5 volts.
8. If voltage is not as noted, replace faulty electrical load detector. If voltage responds as indicated, substitute a known good ECU. If condition is rectified, replace original ECU.
Tuesday, August 23rd, 2011 AT 10:34 PM