[file under "don't fix what isn't broken"]. I'm having a minor issue with a replacement SLABS ECU that I swapped into my 2000 Disco. SLS/ACE/Air Suspension truck. For an upcoming CDL install, I've changed the original SLABS unit that was working fine with one from a 2003 with PN SRD000150. Used Nanocom, got it all set up for air suspension, calibrated height targets, and settings without issue.

With this "new-to-me" 2003 SLABS ECU, I get TC and HDC lamps which is apparently "PWM signal failure from the engine ECU". Thought it might be a loose wire or I hadn't seated a connector properly in the rats nest of ECU wiring, reconnected everything, same error repeatable every time.

Then I swapped back in the original SLABS ECU, no errors. All as it should be.

So - this a bad SLABS? It looked clean, no corrosion on pins, or odd marks. I figured I'd pull it out and crack it open just to be sure no issues from water ingress inside. $120 down the drain from ebay if so.

Anyone have other ideas ? Or just a bum SLABS? There's nothing I can find to indicate the 03 is looking for a signal that's not there on my 00.



(Also programmed a new key and a new green suspension plip. Which is useless but utterly cool.)

 

I would not be surprised the 'new' 2003 slabs compfuser is not compatible with a 2000 Disco main compfuser. Zero data available from the manufacturer keeps them out of lawsuits from accidents caused by tamperers.

 

Baloney.

I have an SRD000150 in my '99 and all is fine.

Also baloney. Ebay has an incredibly buyer-friendly protection policy. Just return the unit as defective, and if the seller won't cooperate file a claim with eBay.

Several years ago a guy bought a TiVo from me on eBay that not only worked fine before I sold it, but passed the deep-dive hard drive diagnostic test with flying colors. The buyer claimed it was defective and I had to eat the sale. At least in your case an eBay claim would be legit. Ebay will require you to first try to work a return/refund with the seller.

Good luck, and let us know how it goes.

 

These ABS units are funny.
I sold an SRD50070 SLABS unit from a UK V8 with SLS to a Guy with a Td5 with SLS and he had all kind of problems with it.
I even programmed the SLABS unit with his personal Td5 VIN and it still never worked though I previously checked the unit on my personal V8 with no SLS and I had no problems.
Needless to say I refunded him his money after 2 months of back to back Email and phone communications and mailing him my Nanocom to sort it it out.

 

Any SLABS unit from 99-04 will work in any D2 NAS V8. I have done many many upgrades for folks & I've done 03-04 SLABS in my 99 D2 & 02 D2 with zero issues and it was completely PNP.

However with that being said it is entirely possible to have a mis-match with say an ECU/Trans ECU/SLABS firmware like any computer based system LR did several TSB for firmware upgrades thru 99-04 to correct small issues. All it would take is a D2 that somehow didn't get upgraded to then be incompatible. I have never run into that on a D2 LR in all my years, but it could happen. Or it's just a SLABS unit with a problem.

 

Thanks. That's all helpful. Running the old one for now and will swap it down the road when my CDL shows up (excited about that !)

 

Well there is some good news. When I went back on ebay (I bought it awhile ago, and I tend to buy a lot of parts late at night after a few glasses of bourbon)... turns out I only paid $30 bucks for it so - no big deal ! ha ha.

 

Following up on this thread with an update. Fast forward to now. Another 2000 D2, ACE/SLS truck. I wanted to add CDL like I did on my previous 2000 D2 5+ years ago.

This truck came with SRD000070, date code 09/02, so it was replaced under warranty recall.

At the PCRC annual chili cookoff and parts swap, someone was selling a used SRD500070 with no corrosion on it, I picked it up for $30. A steal considering most 500070’s online are far more expensive (used or new, and hard to find).

Installed it, fired up the Nanocom, and fully expected the same issues I ran into on my last 2000 when doing this swap, specifically errors and the Engine PWM missing code. The error results from a VIN mismatch between SLABS and engine ECU. There is a way using the LR dealer software Textbook (that probably doesnt exist anywhere really anymore) and a Foxwell NT510 to change the VIN apparently, but I have neither.

It was so cheap, what did I have to lose. I was prepared to cut the wires again. This time, everything was fine.

The new SLABS came from a coil spring truck. I initially saw the same Engine Speed PWM code I mentioned earlier in this thread, which did not inspire confidence, but it said 001 time, and it cleared without returning.

I then changed the setting to AIR and recalibrated the heights. The “ECU Calibrated” status switched itself to Yes.

Works as it should. Observations:
• I get the 3 self test beeps at startup occasionally, not every time.
• Brake pedal feel is slightly softer than before. Subtle, but noticeable. Not necessarily better, in fact I might say worse, but - just different.
• CDL light functions correctly and there are no partial Amigos when the CDL is engaged and the truck is shut off. No need to cut those wires or remember to unlock CDL before turning it off.

Straightforward swap this time around. Much smoother than my previous experience but I am still baffled why some trucks can’t seem to tolerate SLABS swapping without throwing a fit, and others, they swap without issue.


What I saw on the SLABS when I first powered it up in Nanocom

SRD500070 - the new one

SRD000070 - came with the car although not original to the car. I wonder what the velcro is for?

 

Interesting. I don't remember the part number, but I put an early 2004 SLABS in my 2001. It works great but IIRC I did need to cut one wire so that it would work correctly when shutting down and restarting with CDL engaged.