SL-Class (R230) 2003 -- 2012: Discussion on the SL500, SL550, SL600

SL/R230: ECU Pinout

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Old Nov 28, 2019 | 12:04 AM
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SL500
ECU Pinout

Does anyone have a wiring diagram for the connectors to the ECU or a pinout of the ECU? Thanks!
2003 SL500
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Old Nov 28, 2019 | 12:03 PM
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This is the reason I'm asking. I have no STAR software, but curious what this now missing pin this circuit affects.




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Old Nov 28, 2019 | 04:36 PM
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2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Would that happen to be the ECU from an SLK?
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Old Nov 28, 2019 | 04:44 PM
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Originally Posted by Frederick NL
Would that happen to be the ECU from an SLK?
No, it's from SL500.
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Old Nov 28, 2019 | 05:29 PM
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'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
I think the missing pin is a control signal to the engine cooling fan. If so, then I presume your fan always runs and does so at its highest speed.
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Old Nov 28, 2019 | 05:36 PM
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2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Isn’t it frustrating that components seem to be susceptible to penetration of moist. Is a trustable housing and connector really that hard to manufacture...
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Old Nov 29, 2019 | 08:12 AM
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I haven't noticed the fan running on high at all times. I'll have to check to be sure.
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Old Nov 29, 2019 | 09:51 PM
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2007 S65 AMG-Sold, 2007 SL55 P030 - 2016 GL450 - - 2017 AMG GTS - Sold - 2015 AMG S65
I just worked on CL65 and made these pin outs

Originally Posted by Tj Mitchner
Does anyone have a wiring diagram for the connectors to the ECU or a pinout of the ECU? Thanks!
2003 SL500
These may help









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Old Nov 29, 2019 | 10:28 PM
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Originally Posted by Hendrik Koster
These may help









Thanks for the info. If mine is the same as yours, the pin rusted in two is pin 39 on connector 4. According to this, pins 35-40 are not used. That would be great news! Thanks again!
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Old Nov 30, 2019 | 09:34 AM
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'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Originally Posted by Tj Mitchner
According to this, pins 35-40 are not used.
According to the Electrical Troubleshooting Manual all of those pins are used. The engine couldn't start and run without 35 and 36 which activate the motor starter and fuel pumps, respectively.
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