rwyatt365

The reason I'm asking is because I've swapped over all of my "special bits" from a bent '99 (10AE w/ABS), into a straight '00 chassis (w/o ABS) - long story but you're welcome to read all about it here. Basically, everything from the '99 - including the ECU - went into the '00 chassis.

The car is working now with one exception...I keep getting a MIL (P0500), and several of the ECU "readiness monitors" won't go "Ready". The speedo works just fine, but the ECU registers a P0500 (VSS malfunction). With that MIL, the ECU registers "Not Ready" all the time and I can't pass the OBD check.

After tons of reading I'm beginning to wonder if the ECU from my ABS-enabled car is looking for signals from the wheel sensors where there currently are none. But I've pored through wiring diagrams and I can't find anything from the ABS system that feeds into the ECU! In fact, everything I read says that the ABS system is completely separate from the ECU (and I'm tempted to believe that).

However, another data point this morning was when I (finally) displayed the "Speed" signal from the Torque app on my tablet. Lo and behold, it shows zero all the time - even when the speedo registers a speed!!

So...back to the original question; is there a difference between ABS and non-ABS ECU's for NB1's?

18psi

iTrader: (76)

Have tested and made sure the actual speed sensor on the transmission is connected and working?

rwyatt365

It is connected, and the speedometer in the dash works just fine (no fluctuations, no dead spot, and is within 5% of the GPS speed).

18psi

iTrader: (76)

Weird.
Both of them Fed-Spec cars?

swap ecu back and see? 99-00 doesn't have immobilizer so should be easy

rwyatt365

Weird indeed!

Unfortunately to '00 was just a bare shell - no ECU to swap back to ("testers" will be graciously accepted )

aidandj

iTrader: (5)

access to an oscilloscope? Probe the speedo out signal and see what it looks like.

rwyatt365

Got a cheapo scope, will try to scope them tonight.

rwyatt365

The verdict...sumpin goes in, nuttin comes out...

...of the instrument cluster...

What does that mean? The VSS on the trans is good; took it out and it generates a signal at the connector. Put the VSS back in and checked continuity to the dash - checked good. Put the car on the hoist and hooked the scope to the leads from the VSS (1M and 2M), and got a good signal turning the wheels.

THEN, connected the scope to the "speed" output from the instrument cluster (2L), and got...nothing. So, somewhere in the bowels of the signal conditioning in the IC, the speed signal gets "lost".

Time for a new IC...

scenturion

iTrader: (9)

Unfortunately, it's probably your odometer unit, since that converts the VSS signal.
I would be happy to send you a spare for testing for the cost of postage. PM me.