05–2414 DIAGNOSTICS – ENGINE IMMOBILIZER SYSTEM (W/O SMART ENTRY
SYSTEM) 05JGI–01
DTC B2799–539 ENGINE IMMOBILISER SYSTEM
MALFUNCTION
DTC B2799–540 ENGINE IMMOBILISER SYSTEM
MALFUNCTION
DTC B2799–541 ENGINE IMMOBILISER SYSTEM
MALFUNCTION
DTC B2799–542 ENGINE IMMOBILISER SYSTEM
MALFUNCTION
DTC B2799–543 ENGINE IMMOBILISER SYSTEM
MALFUNCTION
DTC B2799–544 ENGINE IMMOBILISER SYSTEM
MALFUNCTION
CIRCUIT DESCRIPTION
These DTCs are detected when: 1) the wire harness between the transponder key ECU and hybrid vehicle
control ECU is open or short circuited, 2) the ECU communication IDs of the hybrid vehicle control ECU and
transponder key ECU are different, 3) the start (ON (READY) signal delayed, or 4) the key codes are un-
matched.
Before troubleshooting for the this DTC, make sure no transponder key ECU DTCs are present. If present,
troubleshoot the transponder key ECU DTCs or hybrid vehicle control ECUs first.
DTC No. DTC Detection Condition Trouble Area
When any of the following conditions are met:
B2799–539 wire harness between transponder key ECU and hybrid
B2799–540 vehicle control ECU is open or short
B2799–541 ECU communication IDs of hybrid vehicle control ECU Wire harness
B2799–542 and transponder key ECU are different Hybrid vehicle control ECU
B2799–543 ON (READY) signal is delayed more than 10 seconds
B2799–544 from when power switch is set to ON (READY)
Key codes are unmatched.
2004 Prius – Preliminary Release (RM1075U)
Author: Date: 2578
DIAGNOSTICS – ENGINE IMMOBILIZER SYSTEM (W/O SMART ENTRY 05–2415
SYSTEM)
WIRING DIAGRAM
T5
Transponder Key ECU Assy
Hybrid Vehicle Control ECU
Center Connector No. 1
26 11 10
R R
IMO H14 4J 4D HEV1
18
18 10 9
W W
IMI H14 4J 4D HEV0
19
B74768
2004 Prius – Preliminary Release (RM1075U)
Author: Date: 2579
05–2416 DIAGNOSTICS – ENGINE IMMOBILIZER SYSTEM (W/O SMART ENTRY
SYSTEM)
INSPECTION PROCEDURE
1 CHECK FOR DTCS
(a) Delete the DTC (see page 05–2351).
(b) Check that no DTC is output.
OK: DTC is not output.
NG Go to step 2
OK
END
2 CHECK WIRE HARNESS (TRANSPONDER KEY ECU ASSY – HYBRID VEHICLE
CONTROL ECU) (TRANSPONDER KEY ECU ASSY OR HYBRID VEHICLE CON-
TROL ECU – BODY GROUND)
(a) Disconnect the T5 and H14 ECU connectors.
Wire Harness Side
(b) Measure the resistance of the wire harness side connec-
T5
tors.
Transponder Key ECU Assy
Standard:
Tester Connection Specified Condition
T5–19 (HEV0) – H14–18 (IMI) Below 1 Ω
T5–18 (HEV1) – H14–26 (IMO) Below 1 Ω
T5–19 (HEV0) or H14–18 (IMI) –
10 kΩ or higher
Body ground
HEV1 HEV0 T5–18 (HEV1) – H14–26 (IMO) –
10 kΩ or higher
Body ground
H14
Hybrid Vehicle Control ECU
IMI
IMO
NG REPAIR OR REPLACE WIRE HARNESS AND
B74765
CONNECTOR
OK
REPLACE HYBRID VEHICLE CONTROL ECU
2004 Prius – Preliminary Release (RM1075U)
Author: Date: 2580
