Diagnose and fix a VW Jetta won’t start condition
If you own a VW Jetta and have a Jetta won’t start condition, read on. If you done any diagnostics on the 2.5L engine, you may have come up with Jetta no start, Jetta no spark, Jetta no injector pulse, no fuel pump and no communication with ECM. The vehicle may start but not restart. If you hotwire the fuel pump relay, the pump will run. But the relay itself doesn’t receive ground from the ECM. The ECM may show a trouble code 01314 no communication with ECM.
Start by checking for power and grounds at the ECM. If they’re good, check for a broken red/black wire from Fuse 10/Fuse box B that goes to pin 62 at the ECM. Shops are reporting problems with this wire. The break won’t be apparent. In fact, the break may be as far as 12″ away from the ECM. Repair that wire and you should be good to go