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I can probably help you, but first I'd need to know what that code number was.
I'm sorry, but I need you to refresh my memory; what and where is relay 428? Also, do you have access to a graphing voltmeter or, better yet, a digital storage scope?
If it's any consolation, this is a paysite and not a forum. All of us experts have been verified as such.
Back to the issue; are you talking about the Power Supply Relay that feeds the positive side of the ignition coils - should be by the brake fluid reservoir and have 5 wires connected to it? If so, check and see if fuse 29 (15A) in the fuse panel is OK.
This issue with the relay should have nothing to do with code P0322, unless the reference signal to the sensor has been lost. Can you check and see it there is any voltage at the Brown and White wires going to the engine speed sensor - try it with ignition on and with engine cranking.
Please let me know what you find.
OK. I still can't remember or even find any reference to a "relay 100", so let's assume it is the Power supply relay which is fed by fuse 29, which also feeds the ECU/PCM. If fuse 29 has no power, that could mean fusible link 176 (110 A) next to the battery is blown. Look at the graphic I've attached and let me know.
After all of that, can we get back to checking voltages at the Brown and White wires going to the engine speed sensor? - try it with ignition on and with engine cranking.
Please let me know the results.
Hey. I just remembered something from years back that use to drive us techs crazy: the grounds under the battery tray (see attached pic.). Make sure to take the time to remove the battery and the tray to clean and redo the three grounds under there - trust me on this one; you won't regret it.
Going by the pic you uploaded, the relay marked 100 is the power supply relay, which we techs know as J271- that's the one that gets is power from fuse 29. The one marked 428 (J299) is just to power the air pump when the engine is cold. fuse 37 (10A) just supplies ignition voltage to the cluster and the radio.
Regarding testing crank sensor circuits, the repair manual tells you to check resistances. Problem with that is that even if the resistances are found to be OK, you don't get to see the actual signal; that's why I recommend using a cheap pc-based scope (less than $100 online) to make sure the engine speed signal is in fact getting to the ECU. Once we know that signal is OK and getting to where it needs to go, we can look at other ECU outputs to see how it is reacting.
Good job on being proactive in taking care of those pesky grounds under the battery!
The reason I said to use a scope is because the readings you took with the Ohmmeter were all over the place. Could you at least see if you can get actual current voltages at the White and the Brown wires to the crank sensor?
Sounds lik you have a good plan. Please let me know if assistance is needed.