Cqdf903u powering on but no sound in 2001 vw jetta

Those sensors wouldn't affect power to the injectors.

You need a voltmeter, it's an electrical problem, so you need a digital volt/ohm meter (DVOM), or also called a multi-meter, and digital because many car circuits that are computer related operate at very low voltages or power demands, from milliamps to thousands of volts, like the ignition delivers to the spark plugs. So you buy a cheap multi-meter, then you also need a wiring diagram for your car to see how the fuel injector circuit works. but start there where you plugged in the new injector harness.

You are looking for power to the injectors, with key on. The injector harness has 8 wires; each injector has a power wire and a ground wire, so 4 of the wires in the harness should have power. At least on most American cars, the injector works by having the ecm control the ground for the injector . The power is constant. It is only when the ecm momentarily internally grounds the injector circuit that the injector fires. On your VW, the injector power wires and ground wires both go to the ecm.

What does fuse 43 power?

There are two problems which might be occurring besides the obvious battery terminals needing to odd wire brushing to expose pure silver lead at the conact posts and inside the post clamps. My 2002 Jetta actually had a crushed wiring harness - Good stuff but it may have been assembled somewhere other than Germany and someone banged the wiring just enough to short or create resistance in the crushed copper. This was solved by a new wiring harness under the hood which also involved the Diesel glow plugs burning up all the time. Second problem may be badly installed diodes in the Alternator. I heard that some have them installed backwards, but only one of them in the group, so of course that would play havock with your charging system even though it will have enough forward power to run your engine. Also the control plug-in wiring on the Alternator sometimes gets salt on it and corrosion then won't let the system be able to get currant to your Alternator to make any power. This is a cheap problem to fix, just buy a new $8 Alternator plug-in and solder it to your wiring cable with good heat shrink wrap insulating tubes and a hair dryer.

the sensor should be located behind the front bumper grill.look through the bumper grill and you should see the ambient temp sender.on the dash,does the display where the temperature used to read have 3 dash lines?if so there is an open circuit in the wiring to the sensor.this will cause the aircon not to work..good luck.

I had the same problem with our 2006 Jetta ... it was the wiring harness in the driver's door. Cost was under $700 bucks installed ... I am in New England.

definatley amp issue there should be a green wire with a red stripe in your harness, if you take the blue wire with a white stripe from the sony deck and hook it up you should have sound. good luck

Your Jetta has two power feeds, one is always live and one is switched.

Unfortunately the color of the wire sometimes varies by model or year so I can't tell you which one.

I assume you're using an aftermarket harness that you've spliced to the kenwood harness. If it came with documentation (the harness), it should tell you which feed is always live and which is switched. if not you can test the leads with a volt meter when the car is on and when it's off.

You most likely have your power line on the Kenwood deck hooked to the line that's always live. Find the switched line, and connect that one instead. Should work.

will it power up at the moment blck wire is always an earth to dash what sort of stereo is this

does the car have an alarm system? if so what kind is it. some alarms prevent the car from starting if it sences a problem. it is possible that you hooked up the stereo and it is causing a malfunction in the starting.

hello chevi1981..what can happen is if whoever installed your system did not run your speaker wires properly eg if they have worn through and touching metal or a screw through the wires ,it can blow the audio ics in unit resulting in no sound.all these high powered units have above ground circuits in the audio stage .to check ,hook up a separate speaker direct to your unit,separate wiring ,if no sound, will most likely be the intergrated circuits..these will have to be changed by a tech as cd players are a beast to work on,also your 2 speaker wires should not touch one another.with your sec code if your have a removable face you may not have a code ,as removing face is your security .hope this helps