U2688 Cadillac Calais OBD Code

OBD/2 U2688 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.

In most cases, the TCM is integrated into a single housing with the PCM. Nevertheless, the section of the module which controls (automatic) transmission function may be powered up separately. In any case, the TCM is typically powered using switched (only present with the ignition switch in the ON, start, or run position) voltage. This circuit is normally equipped with a fuse, fusible link, and/or a relay. Frequently, the PCM and TCM are powered using the same relay albeit by separate circuits. Access to a reliable vehicle information source will yield necessary details of the TCM power circuit for the specific vehicle in question.

U2688 Cadillac Calais Error Code Repair Process :

If your scp (j1850) invalid or missing data for primary id check engine light is illuminated, it's best to take it in for diagnostic testing, which can feel like a hassle. Because while the lights vary in appearance from vehicle to vehicle, all have the same basic meaning: There's a problem with the car's emissions system. The on-board diagnostics system U2688 and engine control unit are in charge of monitoring a bunch of different scp (j1850) invalid or missing data for primary id, and if they get a reading that's a little out of whack, up pops the check engine light.

Common Causes of Cadillac Calais U2688 OBD2 Code

A common cause of code U2688 is the failure of SCP (J1850) Invalid or Missing Data for Primary Id, but there are several other possible causes as well, such as ;

EVAP canister or fuel tank leaks
Faulty Air fuel ratio (A/F) Sensor 1 Bank 1
Ignition coils circuit poor electrical connection
Missing or loose fuel cap

U2688 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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U2688 Cadillac Calais OBD Code

U2688 Cadillac Calais Error Code Repair Process :

Common Causes of Cadillac Calais U2688 OBD2 Code

U2688 code for other Cadillac cars