1991 Jaguar XJ6 CODE Pao

I have a 91 XJ6 Sovereign that is giving me the same code. Jaguar does not even know what it is. Mine is related to a no-start condition. I have it narrowed down to an electrical problem with the fuel system. I get a reading on the positive wire leading into the fuel pump, but nothing on the negative. I think it might be a short in the ground wire, but I am not sure. If you solve your problem, please let me know, because I am completely stumped.

Yes that is the only code that comes up. Neither the Jaguar dealership nor my local foreign car repair shop can tell me what this code means. Ngine will crank and I am getting good spark, but I am getting absolutely no fuel. I just replaced the fuel pump today, and still having no luck. When I test the wiring, I am showing proper voltage on the positive wire to the fuel pump, but no return voltage at all on the negative wire. I thought maybe it was a faulty ground on the negative wire, so I attache it to a new ground and the car still won't start. With the negative wire connected to the new ground, I am getting a FUEL FAIL 22 code which according to the Haynes manual is a open or short circuit in the fuel pump wiring. Please help if you can because if I can't get this car running, I am going to miss out an a job interview for an $18 an hour job. VERY stressed about this.

PAO is not an engine code, but a warning for low brake pads. Your front or rear pads could be worn down, and/or your brake pad sensors could be bad.

A "PAO" warning is not related to a "no start". PAO is low brake pads and or a bad sensor for the pads. Being your car is a Sovereign, I bet when you step on the brake you are getting a red Brake light on the dash that is different than the one that will come on when you pull the emergency brake on.

As to you no start, have you tried spraying starting fluid into the air intake and cranking the motor? If it starts then you have a lack of fuel problem. If the car has been in an accident right before this issue started, you need to check the fuel cut-out switch. If that is good do you hear the fuel pump? If so check your fuel filter. If you do not hear the fuel pump, check the power to the pump. One wire will get power with the key on. The other wire is ground and will not have power. If you have no power at the pump, check your fuel pump relay, (you can swap a similar relay for testing), also check your fuses. If all of those check out ok and you still have no power at the fuel pump, a bad ignition switch can be a cause.

I realize this was asked years ago, but maybe this information will help others.

Thank you I'll check the breaks and let you know what happened