Smart ForTwo Electric Terminal 30 Starting Problems

Having dealt with a similar issue on my 2014 Smart Forfour Electric, I can share some relevant experience as someone with moderate expertise in EV electrical systems. The symptoms you describe match exactly what I encountered. After multiple slow starts, the issue was traced to a failing starter motor, despite having a relatively new battery. The workshop discovered that the continuous power circuit was being affected by a deteriorating connection in the wiring harness, which was causing voltage drops. The fix involved: 1. Complete diagnostic of the charging system 2. Replacement of corroded terminal connections 3. Testing the ignition switch for proper function 4. Installing a new starter motor assembly Total cost was 290€ including parts and labor. Since the repair, starting has been consistently strong with no issues. Before suggesting specific solutions, could you share: Any warning lights on the dashboard? Does the problem occur more after the car sits for several days? Have you noticed any electrical accessories behaving oddly? What voltage reading do you get across the battery terminals? This information would help determine if your issue matches what I experienced or points to a different electrical problem.

Thanks for sharing your expertise. After a recent service at 79128 KM, the mechanic actually found that my fuse box had several loose connections affecting the power supply. When testing voltage drops across various circuits, they found inconsistent readings at the main terminal blocks. The starter motor bench test showed normal function, but the circuit breaker controlling that circuit was triggering intermittently. We traced the wiring harness path and found a spot where it was rubbing against the frame, causing intermittent shorts. The voltage readings you mentioned helped point us in the right direction. No warning lights appeared during any of these issues, which made initial diagnosis tricky. Based on actual readings from our fix: Battery: 12.6V at rest, Starter draw: Normal range, No voltage drop at terminals, Circuit resistance: Within spec after repair

Glad to hear you got to the bottom of the issue. Your experience matches the pattern I noticed, these electrical gremlins often hide in the fuse box and wiring connections rather than the obvious components. The consistent 12.6V battery reading was a good indicator that the power supply itself was solid. The rubbing wiring harness you found is particularly interesting, I had a similar wear point develop near my starter motor mounting bracket. These contact points can create voltage drops that are hard to trace without systematic testing. The circuit breaker behavior you described mirrors what my mechanic found during diagnostics. Did they apply any protective sleeve to the harness where it contacts the frame? After my repair, the workshop added split loom tubing at wear points to prevent future issues. Also worth checking the ignition switch wiring while everything is apart, these can develop high resistance over time even when the switch itself tests good. The intermittent nature of your problem definitely matches the pattern with compromised power supply circuits. Good catch on doing the full circuit diagnosis rather than just replacing parts. Testing the complete electrical path from battery through fuse box to starter motor often reveals these hidden issues that cause slow cranking.

Thanks for the comprehensive replies and diagnostic suggestions. Your experience helped navigate this issue effectively. The shop did add protective sleeving to the wiring harness where it contacts the frame, plus they secured additional mounting points to prevent future rubbing. The voltage drop testing across the power supply circuit really proved crucial. With the fuse box connections tightened and the wiring harness properly protected, the starter motor now engages consistently with normal cranking speed. This matches what you found with your repair. Full repair breakdown: New mounting clips for wiring harness: 15€, Protective sleeving: 25€, Circuit breaker replacement: 45€, Labor: 180€ Testing confirms all electrical values remain stable: Battery maintains 12.6V, No unusual voltage drops, Starter motor draw stays within spec, All fuse box connections tight Really appreciate the suggestion to check the complete electrical path. Would have been easy to just throw parts at the problem, but systematic diagnosis of the power supply system found the real cause. The car starts perfectly now at 79500 KM.