If this deficiency is detected in connection with the above error codes, it may be caused by a short-circuit in an injection valve (Fig.1).
This deficiency frequently occurs in vehicles with more than 100,000 km on the clock.
After replacing the defective injection valve you should check that the endstages in the electronic control unit (Fig.2) are functioning correctly and check the injector cable harness (Fig.3) for possible cracks or damaged contacts. To avoid further damage, when an injector valve fails it is advisable to check, and if necessary replace, all the other injector valves that have the same code number, because it can be expected that these may be the next to fail.
Please do this by following the disassembly and reassembly instructions from the vehicle manufacturer.
Important safety note
Not helpful at all