QX4 Dilemma

[jimdoe]

a few days ago my suv died while running. before it happened, the power (ie interior lights, cig lighter to my ipod, cd player) started cutting off and then it went dead. Thought it was the battery because the inside lights, panels, and win power was low, so had it jump started, but it only clicked and did not even cranked. After a couple of tries it finally started and died again on the way to the shop. Next day at the shop, mech replaced the battery b/c it was not charging. Also replaced the alternator b/c it was bad. Other than those two it was running again, till late today. My bro drove it away from the city late today, long and behold, same crap happened. now it won't even start no matter what. Well, I know there are still a lot of things that can be done, but has anyone experienced this kind of problem before?Oh, also, on the night it first happened, after the first jump start, if don't keep the engine rev up it would die. So i had to maintain above 1krpm. And the engine was struggling when it ran. So, if anyone has any idea what to do next, your replies would be appreciated.

TY in advance.

[ARKQX33V6]

All cables need to be verified. The low voltage output from either alternator and/or either battery gives a low voltage input to the ECU and at less than 5 V the processor's algorithms will be at risk, so all outputs as in fuel etc will be lost even the limp home mode. All grounds need to be verified especially battery , alternator and ECU.

The door locks and theft inhibitor may be the reason. What was the condition of the battery and alternator that was removed? You must know in order to diagnose, you want an unbiased look at them.

A lot of relays etc are interlocked to the ignition gas to delay theft. If the problem is intermittent and not causing the shut down diagnoses can be a long time effort.

Check any and all fuses, fuse links that control the main bus to the fused circuits.

My schematic shows sub circuits (97 QX4) that if fuses are out will cause what you describe. Have any fuses been replaced, or fuse links?