Mine is Corolla SE Saloon auto. 1993.
I doubt came with genuine 4E-FE.
Previous owner replaced it with 5A-FE (may be).
Now the ACU is 5A-FE, and the engine is 4A-FE (16 Volvo 1.5)
The problem arrived after I put engine from pindi.
Error code 42.
Speedometer and trip works fine. Never shows problem.
If I drive it on soft panel, (non aggressive) it works fine.
But when I run on heavy feet (driver speaking ) each gear shift is above 3500 rpm approx. and check engine light is comes every time I run heavy. It shows up on 3rd gear and above (auto transmission, so 3rd gear is not must).
I have checked error code many times and it is 42.
Replaced speed sensor in gear with a qabli, same looking piece. But again light shown up on test drive. (Then I returned the sensor and put back my own)
The question is, if gear shifts are good and speedometer is good, where is the problem even I replaced VSS.
Is there any compatibility issue with 5a's ACU with 4a's VSS?
Error Code: 42 Description: No. 1 Vehicle Speed Sensor Circuit. Probable Causes:
• Vehicle speed sensor
• Combination meter
• Harness or connector between vehicle speed sensor and ECM. Loose, contaminated or corroded connectors.
• ECM NOTE: The No. 1 vehicle speed sensor outputs a 4–pulse signal for every revolution of the differential case.
After this signal has been converted into a more precise rectangular waveform by the waveform
shaping circuit inside the combination meter, it is then transmitted to the ECM.
Hi brother, please find a brief description of your fault.
Error Code: P0720 Description:
Output Shaft Speed (OSS) Sensor - Circuit Malfunction Possible Causes:
Vehicle speed (VSS) sensor.
Engine control module (ECM)/Powertrain control module (PCM)/Transmission control module (TCM).
Output shaft speed sensor or counter shaft sensor is a 3- pin sensor which is located on the transmission. Check carefully one or more of its wires for disconnection or corrosion in the connector.
For this to approach you have to take the whole air filter box out.
Hope that works. If the problem persists, please let me know.