Toyota 88-94 Land Cruiser 4.0L OBD1 Codes

Accessing – MIL

Switch ignition ON
Check MIL illuminates
Start engine. Allow to idle.
If MIL extinguishes, no trouble codes have been recorded.
If MIL remains illuminated, access trouble codes.

Accessing – Trouble Codes

Switch ignition ON. Do NOT start engine
1988-90 – jump DLC terminals T and E1 with a short lead 1
1991-94 – jump DLC terminals T and E1 with a short lead 2
Count MIL flashes and compare with trouble code table
First flashes of 0.5 second duration indicate ‘tens’, after a 1.5 second pause, next flashes of 0.5 second duration indicate ‘units’
A 2.5 second pause occurs between codes
After a 4.5 second pause, trouble codes will be repeated
The MIL flashes once every 0.25 seconds if the system is correct
Switch ignition OFF
Remove jump lead

Clearing Trouble Codes

After the faults have been rectified, erase the trouble codes as follows:
1988-90 – remove EFI fuse (15A) from LH fascia panel fusebox for 30 seconds minimum 5
1991-94 – remove EFI fuse (15A) from underhood fusebox for 30 seconds minimum 6
Reinstall fuse
Repeat accessing procedure to ensure no data remains in ECM fault memory

Trouble Codes

88 – 94 Land Cruiser 4.0L Engine Code: 3F-E
Trouble code	Fault location	Probable Cause
11	Engine control module (ECM) power supply	Wiring, ignition switch, engine control relay, ECM
12	Engine speed (RPM) sensor -circuit	Wiring, RPM sensor, ECM
13	Engine speed (RPM) sensor -above 1000 rpm	Wiring, RPM sensor, ECM
14	Ignition reference signal -no signal	Wiring, ignition module/coil, ECM
21	Heated oxygen sensor (H02S) 1 circuit	Wiring, H02S, ECM
22	Engine coolant temperature (ECT) sensor circuit	Wiring, ECT sensor, ECM
24	lntake air temperature (IAT) sensor circuit	Wiring, IAT sensor, ECM
25	Mixture control -continuously lean	Wiring, injector, H02S, ECT/VAF sensor, intake/fuel/ignition system, ECM
26	Mixture control -continuously rich	Wiring, injector, fuel system, cold start injector, H02S, ECT/VAF sensor, ECM
28	Heated oxygen sensor (H02S) 2 circuit	Wiring, H02S, ECM
31	Volume air flow (VAF) sensor -circuit	Wiring, VAF sensor, ECM
32	Volume air flow (VAF) sensor -circuit	Wiring, VAF sensor, ECM
35	Barometric pressure (BARO) sensor-circuit	ECM
41	Throttle position (TP) sensor -circuit	Wiring, TP sensor, ECM
42	Vehicle speed sensor (VSS) -circuit	Wiring, VSS, ECM
43	Starter signal -circuit	Wiring, ignition switch, ECM
51	Switch signal -A/C switch ON during diagnosis	Wiring, A/C switch, A/C amplifier, ECM
51	Switch signal -closed throttle position (CTP) switch OFF during diagnosis	Wiring, CTP switch, ECM
51	Switch signal -park/neutral position (PNP) switch not in P or N during diagnosis	Wiring, PNP switch, ECM
52	Knock sensor (KS) 1 -circuit	Wiring, KS, ECM
53	Knock control -malfunction	ECM
55	Knock sensor (KS) 2 -circuit	Wiring, KS, ECM
71	Exhaust gas recirculation (EGR) system -malfunction	Hose leak/blockage, wiring, EGRT sensor, EGR solenoid, ECM
81	Transmission control module (TCM) -communication	Wiring
83	Transmission control module (TCM) -communication	Wiring
84	Transmission control module (TCM) -communication	Wiring
85	Transmission control module (TCM) -communication	Wiring