Electronic Accelerator (EA) - Who's got the best price?

[Justin_Luhrs]

Hello all,

Ruf has confirmed they have the TPS sensors, but they will not sell them to me.

With that in mind, I'll continue to look at redesign of that area should the need arise.

I have been purchasing teflon wire on ebay, as that seems to be the least expensive way to get smaller quantities.

My unit contains to following gauges: 16, 18, 20, 22

The motor wire is 16, the cross harness wiring is 22, while the 18 and 20 gauge wire make up the rest of the external wiring harness.

I'll drop another post when I have more for you!

Thanks again to myarmar for putting up that gauge conversion link, it made things pretty painless!

Justin

[Strife]

I have a good supply of Teledyne Thermatics 22ga(possibly-MIL spec part number) teflon/tefzel wire I'd contribute to this Great Experiment.

[Justin_Luhrs]

Thanks strife, I already had won 50ft of ten different colors of 22 gauge by the time you'd posted, but I'm sure one of us will be able to use it.

Tefzel is the preferred jacket material, that's the one the aircraft industry and military use today. Not sure what the difference is between that and straight teflon insulation, but the mil spec would explain the differences I'm sure.

I don't anticipate any problems with the jacket though, there are no tight bends in the ass'y, nor are there any high voltages present.

Hopefully all my wire will arrive by weeks end so I can finish these units and get her back running!

Justin

[Kebowers]

Could you please do a wiring diagram--which connector pin number went to where? I have an ETA where there are no recognizable colors left and I hate to do a 10! (10 factorial) experiment to sort them out.

BTW the main wiring harness is only about $3000 now.Prices skyrocketed in the past year.

[JimF]

Originally Posted by Kebowers

Could you please do a wiring diagram--which connector pin number went to where? I have an ETA where there are no recognizable colors left and I hate to do a 10! (10 factorial) experiment to sort them out.

. . . Menu#24; there's a schematic of the ETA with wire colors, courtesy of myarmar.

[Justin_Luhrs]

Heh.. yeah I had that problem bad. I just wrote down what they resembled to me at the time, after I matched them up with the ESM wiring diagram I was certainly surprised!

When I'm done being lazy, I'll post pictures of my physical wiring drawings, the diagram does a couple of weird things that can confuse you at first glance.

That diagram myarmar put up is a little hard to read, I'll throw a full size one up on my site tomorrow. I know he has the good ones, but I don't think he has a place to post them, and I've got plenty of space. The ESM version has the wires in their respective colors on the diagram, which is handy.

(here it is: EA Wiring Diagram & EA Connector Diagram - '93 600SL) (Best viewed at 1280x1024)

Also, my 22 and 20 gauge wire arrived today, and a thermal stripper I borrowed looks like it's going to do the trick just nicely.

Here are the wire counts:

Left side ETA (right side of engine):

9 wires, 22 AWG/0,35 (from TPS to sub circuit board)
7 wires, 20 AWG/0,5 (wiring harness, to sub circuit board)
2 wires, 18 AWG/0,75 (wiring harness, to sub circuit board)
2 wires, 16 AWG/1,5 (wiring harness, direct to motor)

Right side ETA (left side of engine)

9 wires, 22 AWG/0,35 (from TPS to sub circuit board)
4 wires, 20 AWG/0,5 (wiring harness, to sub circuit board)
2 wires, 18 AWG/0,75 (wiring harness, to sub circuit board)
2 wires, 16 AWG/1,5 (wiring harness, direct to motor)

[Justin_Luhrs]

What year is your car? My harness is P/N: 129-540-71-05, retail price is $805. I can get it wholesale probably high 6's. I checked price last in December.

You need the harness in the engine compartment only, not the rest of the car. I'm sure the one inside the car is a doozy.

Let me know if you were looking at the wrong harness or if someone is trying to check your shoe size!

Justin

[myarmar]

This harness P/N: 129-540-71-05 is on the top of the engine and includes injectors, camshaft solenoids, and temp. sensors only. Unfortunately you need body mounted engine harness, probably 129 540 1506, retail $2240 in 2001 EPC.

[Justin_Luhrs]

That's interesting... I wasn't quoted that harness when the vehicle was inspected, but if it includes the wiring to the EAs... I'll probably need it.

Ouch!

I guess I'll do some inspecting on the other side of the connector, hopefully (but doubtfully) it has faired better.

[LeaUK]

Justin

I've just read an interesting post by another member noting that Benz started considering biodegradable systems (including cable looms) around 10 or so years ago: Readout codes for SL600

Out of interest, does your loom show any manufacturer's coding as we could look up the original specs?

Cheers
Lea

[Justin_Luhrs]

I've heard the same rumor, but I don't personally believe it. Mercedes knows that the service life of their vehicles is significantly higher than most "mass market" cars. I think this was probably just an engineering mishap, where the long term performance of the wire was misconsidered.

Either way, we're never going to get an official answer out of anyone. Nobody will admit to a mistake, and if they did intentionally design the wire this way, they will have had to make their replacement parts out of different wire, which I'm not at all sure they have.

Better to make the part once, then have it replaced three times, after all... which is going to produce more waste?

After smoking crack all day today, I'm seriously condisering rebuilding the whole harness if I find it is necessary.

I'd rather spend a $1K and a lot of time and do it right and never have to do it again then be forced to pay exorbitant amounts of money time after time for such a simple issue.

When I'm under the hood again I'll look for any identification, but I doubt will find anything (it is probably Bosch wiring, but who knows where they got it from).

[LeaUK]

Most Manufacturers stamp their identifiers on the insulation so it would be worth having a peek.

I assume the $1000 comes your your costs of replacing all the wiring, including engine harness and connectors - are you considering an MB part for the engine harness? Is it too complex to replace simply the wire?

Does the harness travel around the engine having propriatory connectors?

Cheers
Lea

[Justin_Luhrs]

Originally Posted by LeaUK

Most Manufacturers stamp their identifiers on the insulation so it would be worth having a peek.

I assume the $1000 comes your your costs of replacing all the wiring, including engine harness and connectors - are you considering an MB part for the engine harness? Is it too complex to replace simply the wire?

Does the harness travel around the engine having propriatory connectors?

Cheers
Lea

The insulation on the wires inside the EA units have no nomenclature on them.
I'm guessing the rest of the wiring would be the same. I've seen a lot of wiring in a lot of other car harnesses, and it usually lacks any information. None of the teflon wire I purchased has any nomenclature on it either. $1000 would be an approximate cost for wire only (and just a rough guess), and with the supposition that I could re-use all proprietary connectors. The connectors I don't believe are available separately, but since I found a way (albeit ugly) to reuse the ones on the EA harness, I'm supposing I could probably do the same for the rest. It would be a pretty time consuming job, but people who restore classic cars have to do it all the time, so it's not impossible. I'd probably use tefzel for all the wire, teflon heat shrink where necessary, and silicone insulation tape for the overwrap.

It's just obvious to me at this point that MB is making a mint on these parts, as there is no special reason for these parts to be so expensive. There is practically nothing to the EA units themselves, certainly not $3K worth of parts. And a wiring harness is just wires with some ends on them. Engine and transmission parts are one thing, but other simple parts have no reason to be worth half the cars value or more. And yearly increases in these prices goes further to show this is a huge profit center for them, as I doubt the prices are going up strictly because there is a limited supply of parts that are running out. The car just isn't old enough for that yet.

Another update:

The gentleman who had his EA up for auction on ebay has sent it to me for testing. I received it today. I will probably pull the covers off tomorrow and check it out, I'll post the results when I do.

The soon to be wire king,

Justin

[Kebowers]

When I found out 3 years ago that my newly acquired 94 sl-600 had bad ETA's, I went into a real funk. Then I started researching (I had replaced the injection wiring harness B4 purchase) I went looking--and found missing insulation on lots of wires in the engine compartment--then checked the ETA bundles. Inside the covering there was just crumbled old PVC dust--and bare corroded wires. Then I really started hunting. I had known about the Volvo wiring harness problem from replacing them on all 3 Volvos in our family. In all seriousness, Bosch&MBS used biodegradeable wiring harness insulation starting in late 91 or early 92--and continued with that formulation until sometime in 95. The formulation was failing early in service life. It is a KNOWN problem ----known to Bosch and MBZ.

Lots of ETA's have been replaced due to failed insulation in the harness. Lots of costly electronic modules have been damaged by wiring shorts. The owner is not told of the root cause. He/she is presented with a large bill to pay--for wiring harness and module replacement. If they complain effectively and loudly (and have had their car 'serviced' by that Dealer from whom they bought it--SOMETIMES MBZ picked up all or part of the tab.

This IS NOT an isolated/rare/random failure--all the ETA's and wiring harnesses are failing from this insulation failure.
Deterioration of wiring harness like this IS NOT NORMAL and SHOULD be subject of a massive recall. MBZ has resisted and probably applied lots of pressure through political clout on the NHTSA to avoid a recall. They claim this is not a safety issue.

[myarmar]

The ETA cables in my car (92 600SEL) have KROSCHU mark http://www.kromberg-schubert.com/ (Kromberg & Schubert GmbH). No sign of insulation problem here.