U3128 Mazda Grand OBD Code

OBD/2 U3128 error code description and symptoms.

Low Speed Fuel Pump Primary Circuit Malfunction The PCM monitors the low speed fuel pump (LFP) primary circuit output from the PCM.
The test fails if: When the LFP circuit is commanded on (grounded), excessive current draw is detected on the LFP circuit; or when the LFP circuit is commanded off, voltage is not detected on the LFP circuit (the PCM expects to detect VPWR voltage coming through the low speed fuel pump relay coil to the LFP circuit). Open or shorted low fuel pump (LFP) circuit Open VPWR to low speed fuel pump relay Damaged low speed fuel pump relay Damaged PCM An open circuit or short to ground can only be detected with the low speed fuel pump.

As long as the throttle plate remains closed, the idling speed and quality is controlled by the PCM via the idle control valve, and as can be seen from the above it should be clear that idle control on a gasoline engine is a complex affair. For instance, if the engine is started in sub-zero temperatures, the PCM will command the idling control valve to allow less air to enter the engine to enrich the air/fuel mixture to create a condition which is roughly analogous to how chokes worked on carburetted engines to control idling in cold weather.

U3128 Mazda Grand Error Code Repair Process :

The scent may U3128 signal oil or coolant leaking from their normally closed-loop systems, or it may indicate dangerous exhaust gases invading your car's interior. Car and truck exhaust contains toxic gases such U3128, so if the inside of your car exhaust pressure control valve range/performance as if you were standing behind your car, get out and get it fixed. Fight the urge to take a little nap first. So sleepy. That's the carbon monoxide talking, friends. At least open a window on your way to the shop.

Common Causes of Mazda Grand U3128 OBD2 Code

A common cause of code U3128 is the failure of Exhaust Pressure Control Valve Range/Performance, but there are several other possible causes as well, such as ;

EVAP canister or fuel tank leaks
Faulty Air Flow Meter
Fuel tank leaking
Faulty Fuel injector

U3128 is a kind of Network Trouble Code

U-code indicates that engine communication errors and shows lost communication with engine parts.U-Codes are fairly straight forward, given all of the articles and technical publications that have been written regarding these problematic codes. In most cases, it just comes down to identifying the module that isn't communicating with the other modules on the CAN bus line for whatever reason.

Engine OBD 2 Codes website is a freeware resource center for engine trouble codes.

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U3128 Mazda Grand OBD Code

U3128 Mazda Grand Error Code Repair Process :

Common Causes of Mazda Grand U3128 OBD2 Code

U3128 code for other Mazda cars