Electricity problems with CLK year 2000
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Joined: Jun 2025
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W208 year 2000 3.2l v6 auto
Electricity problems with CLK year 2000
Hi,
greetings from Finland. I have year 2000 CLK, 3.2l v6 aut. Driven about 152 000km. I have problems with it and I have done a quite much investigation together with an AI. Please see below the results.🧾 W208 CLK Parasitic Draw Diagnostic Summary
Owner: Autio Vehicle: Mercedes-Benz W208 CLK Issue: Excessive battery drain when parked Normal Draw Target: ~0.04–0.05 A Original Draw: ~0.57 A
✅ Final Diagnosis Overview
Status
Total Draw
Notes
All fuses removed
~0.04 A
Healthy sleeping current
All fuses in
~0.57 A
Excessive draw diagnosed
Problem fuses removed
~0.05 A
Acceptable resting state achieved
🔌 Fuse-Level Draw Findings
Trunk Fuses
Fuse
Draw (A)
Systems Powered
Remarks
5
0.34
Trunk light
Light stays on; switch misreads closed trunk
6
0.09
PSE, alarm prep (possible)
Suspected partial wake trigger
9
0.09
Interior lighting delay
Light/delay module may stay awake
10
0.09
Soft top ECU, rear SAM
Could be retaining memory or misfiring
11
0.09
Comfort access, antenna amp
Potential for backfeed
Under-Hood Fuses
Fuse
Draw (A)
Systems Powered
Remarks
8
0.10
Seat/mirror adjustment (L), heater, locking
Comfort module may stay live
17
0.10
Seat/mirror adjustment (R), heater, locking
Mirror heater logic may be affected by ambient sensor
26
0.42
Instrument cluster, HVAC panel, residual heat
Major draw—cluster or heater system not sleeping
41
0.10
Residual heater, horn, rear defroster
Heater pump likely culprit
🧩 Connected Issues
greetings from Finland. I have year 2000 CLK, 3.2l v6 aut. Driven about 152 000km. I have problems with it and I have done a quite much investigation together with an AI. Please see below the results.🧾 W208 CLK Parasitic Draw Diagnostic Summary
Owner: Autio Vehicle: Mercedes-Benz W208 CLK Issue: Excessive battery drain when parked Normal Draw Target: ~0.04–0.05 A Original Draw: ~0.57 A
✅ Final Diagnosis Overview
Status
Total Draw
Notes
All fuses removed
~0.04 A
Healthy sleeping current
All fuses in
~0.57 A
Excessive draw diagnosed
Problem fuses removed
~0.05 A
Acceptable resting state achieved
🔌 Fuse-Level Draw Findings
Trunk Fuses
Fuse
Draw (A)
Systems Powered
Remarks
5
0.34
Trunk light
Light stays on; switch misreads closed trunk
6
0.09
PSE, alarm prep (possible)
Suspected partial wake trigger
9
0.09
Interior lighting delay
Light/delay module may stay awake
10
0.09
Soft top ECU, rear SAM
Could be retaining memory or misfiring
11
0.09
Comfort access, antenna amp
Potential for backfeed
Under-Hood Fuses
Fuse
Draw (A)
Systems Powered
Remarks
8
0.10
Seat/mirror adjustment (L), heater, locking
Comfort module may stay live
17
0.10
Seat/mirror adjustment (R), heater, locking
Mirror heater logic may be affected by ambient sensor
26
0.42
Instrument cluster, HVAC panel, residual heat
Major draw—cluster or heater system not sleeping
41
0.10
Residual heater, horn, rear defroster
Heater pump likely culprit
🧩 Connected Issues
- Ambient temp sensor (front bumper): History of malfunction → may trigger mirror heaters (F8/F17) and residual heat logic (F26/F41)
- Cluster wake signal (F26): Prevents CAN sleep → causes draw across other fuses
- Soft top ECU & PSE (F10/F6): Systems known to stay active longer than they should
- Interior delay relays (F9/F11): Can hold voltage longer if capacitor/memory circuit fails
- Repair or adjust trunk light switch/latch
- Consider isolating mirror heater circuits if ambient temp errors continue
- Unplug or test cluster, PSE, soft top ECU individually to confirm sleeper draw
- Evaluate replacing or disabling residual heater relay/module if not used
Thread Starter
Newbie
Joined: Jun 2025
Posts: 2
Likes: 0
W208 year 2000 3.2l v6 auto
AI was quite eager to think trunk light is faulty, but it is not. This car is mystery case, but when I measured yesterday I was able to get some results:
The problem fuses that draw current are:
Trunk fuses
5,6,9,10,11
Under the hood fuses
8,17,26 and 41
So quite a list. I think they are connected somehow. When those fuses are NOT in place, the current draw is around 0.05 A, this is ok I think.
The problem fuses that draw current are:
Trunk fuses
5,6,9,10,11
Under the hood fuses
8,17,26 and 41
So quite a list. I think they are connected somehow. When those fuses are NOT in place, the current draw is around 0.05 A, this is ok I think.
