i was running my 04 xtype in park servicing the airconditioner for approx. 2 hours when the car started running very poorly and the radio and all electrical items shutoff. the car was still running. i switched off the car and hooked up my obd2 scanner. i got only a p1000. now the car will not start, will not motor it just clicks one time. ive searched for disconnected wires and lines but found nothing. when it was running the temperature gauge was reading normal. Anybody know what to do here?

 

sbrantley, what it sounds like you had happen is that you overloaded the alternator and you essentially were running off of the battery and you drained that too. I would first take a multimeter and with the car off, connect the multimeter across the battery to see what its voltage is. It should be up at 12.6 VDC. If you are down around say 12.3 VDC or lower, then you definitely have a discharged battery. Recharge the battery and see what the car does then.

If the battery is up at 12.6 VDC (before or after the recharge) and the car will still not start, then connect a multimeter across the battery and watch it as you attempt to start the car. As you are attempting to crank the car, does the multimeter drop to about 11.0 VDC? If the multimeter drops to around 11.0 VDC and the motor cranks over, then you simply had a battery that was drained or the problem has resolved itself. If the battery stays up around 12.0-12.6 VDC, then you have a bad battery cable (positive or negative cable) and you need to replace the cable(s). If you want to figure out which one is bad, let me know. If the voltage fell to below 11.0 VDC (normally will hit in the neighborhood of 10.0 or less), then you have a bad battery and what took it out was being subjected to the high heat of having the car sit idle. Replace the battery.

Hope this helps you find your problem.

 

i connected the multimeter as you said and it read 9.58.

 

i replaced the battery and took the car to Oreilly's and the guy hooked up the tester and said the diodes and regulator were good but it had a low output,only 13.2v.

 

sbrantley, the Jag programming of the alternator is a little goofey to those not familiar with it. Keep an eye on the battery and go from there. I think you will find out that the car will perform flawlessly from here on out. if you are truely worried about the alternator. What you should see with the multimeter is when you start the car, the multimeter will drop to around 11.0 VDC as you are cranking the car. As soon as the motor catches, the alternator output is going to shoot up to around 14.5 VDC (yes, 14.5). It will hang there for a short period of time and then it will fall down to around the 13.4-13.7 VDC range. Depending on what the car is seeing as loads running, the voltage may shift a little bit more from there. So, what you are seeing is "normal". But to the average mechanic not familiar with Jags, it will seem a bit odd.