Question about 1990 Lexus LS 400
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Posted on Jan 02, 2017
WE ARE AN AUTO REPAIR SHOP IN ROCK HILL SC. WE HAVE RUN INTO THIS PROBLEM BEFORE. WE CAN REPAIR THIS, PARTS AND LABOR APPROXIMATELY 625.00, WITH A 12/12 WARRANTY. CONTACT EAST COAST PERFORMANCE AT 803-329-3868
Posted on Nov 19, 2009
It is either your Vehicle Speed Sensor (easy to change) or your Automatic Transmission Computer (capacitors burn out on these boards, there is a fix for this too, the picture is at the bottom of this page). You need to diagnose by removing the lower right plastic kick panel on the passenger side. There you will find a blue plug. With the car OFF stick a paper clip, wire or stuff the plug with foil to make electrical connection so that the two terminals are touching. Then, turn the ignition to ON (not enough to start it though, just power it up). When you do this, count the blinks in the "D Light" or count your blinking Check Engine Light. Both are different but can refer to different things wrong with your car. A long blink is the first number and the short blinks that follow are the second number.
So imagine this as being 14 : ___ _ _ _ _
Below is a decoding chart:
The first section will be the check engine light codes, the next one is the Transmission Control Unit Codes read from the D Light;
1 O2A - Oxygen sensor #1
2 O2B - Oxygen sensor #2
3 MAP - manifold absolute pressure sensor
4 CKP - crank position sensor
5 MAP - manifold absolute pressure sensor
6 ECT - water temperature sensor
7 TPS - throttle position sensor
8 TDC - top dead centre sensor
9 CYP - cylinder sensor
10 IAT - intake air temperature sensor
12 EGR - exhaust gas recirculation lift valve
13 BARO - atmospheric pressure sensor
14 IAC (EACV) - idle air control valve
15 Ignition output signal
16 Fuel injectors
17 VSS - speed sensor
19 Automatic transmission lockup control valve
20 Electrical load detector
21 VTEC spool solenoid valve
22 VTEC pressure valve
23 Knock sensor
30 Automatic transmission A signal
31 Automatic transmission B signal
36 traction control found on JDM ecu's
41 Primary oxygen sensor heater
43 Fuel supply system
45 Fuel system too rich or lean
48 LAF - lean air fuel sensor
54 CKF - crank fluctuation sensor
58 TDC sensor #2
61 Primary oxygen sensor
63 Secondary oxygen sensor
65 Secondary oxygen sensor heater
71 random misfire cylinder 1
72 random misfire cylinder 2
73 random misfire cylinder 3
74 random misfire cylinder 4
80 Exhaust Gas Recirculation insufficient flow detected
86 ECT Sensor (Engine Coolant Temperature) circuit range / performance problem
90 Evaporative Emission Control System leak detected in the fuel tank area
91 Fuel Tank Pressure Sensor low input
92 Evaporative Emission Control System insufficient purge flow
1-Lock-up solenoid 'A' circuit open or shorted.
2-Lock-up solenoid 'B' circuit open or shorted.
3-Throttle Position Sensor circuit open or shorted.
4-Vehicle Speed Sensor open or shorted - No signal from speedometer.
5-Shift Lever Position Switch circuit shorted.
6-Shift Lever Position Switch circuit open.
7-Shift Solenoid 'A' circuit open or shorted.
8-Shift Solenoid 'B' circuit open or shorted.
9-Counter shaft or transmission speed pulse generator open or shorted.
10-Coolant Temperature Sensor open or shorted.
11-Engine RPM (Ignition coil signal) open or shorted.
12-(No code 12 used)
13-Main shaft speed pulse generator open or shorted.
14-Linear (line pressure control) solenoid open or shorted.
15-Kick down switch circuit shorted.
Posted on Feb 14, 2010
Testimonial: "Thanks this was verry helpfull it came up the transmission speed pulse generator code."
My sincere apologies for the delayed response.
I am personally going back to answer your unanswered questions.
I have only been a free contributor to this site for the past 4-months.
I do not know if you still need this information, but I am going ahead and answering it anyway.
For the 4.0L DOHC 8-Cylinder:
(back of engine)
(front of engine)
Again my apologies...
Let me know if this helped, or if you have any additional information or questions. Feel Free to contact me at FixYa.com!
Posted on Mar 11, 2010
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