Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
About 4 months ago I bought this car, drove great and everything worked. 2 months ago the fuel pump went out so I replaced it myself. It drove great after replacing it. One morning I go to leave for work and it cranks doesn't start. So I started testing everything (hadn't bought a code reader just yet) battery, starter, relays, sensors, injectors and everything works. So I figured it was a ground somewhere, cleaned all connections. Still cranks no start. Finally bought a code reader and it's reading a P1682 (ignition 1 circuit 2). I checked ignition switch and the connector, all good there. I don't have any ignition power to the run/crank relay which also trickles down to my fuel pump not kicking on. So while checking wires (haven't removed anything or disconnected anything, just figuring which wires go where with schematics) my car put itself into anti theft mode. I have interior lights, window power, headlight/tail light power. When i turn the key the only thing that comes on is the anti-theft light (shuts off a few seconds later) and odometer.Where do I even start?? I can't connect my code reader because there is no power to the OBD2. I need some serious help and ASAP please!!!
Last edit: 2 years 3 weeks ago by Sammyjammy406. Reason: Forgot to mention testing ignition switch.
You need a good wiring diagram to see what all is on ignition 1, circuit 2. You also need to find out where the power for pin 16 in your DLC comes from to find out why you don't have power there. If you can't restore power to your DLC, you can probably run a fused jumper wire from the positive side of the battery to pin 16 of the DLC with a back probe so that you can get power to your scan tool and see if you have any other codes now. If your fused jumper wire blows, then you know you have a short to ground on that circuit.
