Experiencing a no-crank situation with your vehicle can be incredibly frustrating, especially when you expect the onboard diagnostics system to provide some clues. The scenario often involves reaching for your OBD2 scanner, anticipating a wealth of diagnostic trouble codes (DTCs) to guide your repair process. However, what happens when you plug in your scanner and are met with a perplexing message: “No codes are stored in the module”? This situation, while seemingly contradictory, is more common than you might think and can point towards specific types of automotive problems.
The Frustration of Silence: No Crank, No Codes
Imagine this: your Ford vehicle refuses to start. You turn the key, and nothing – just silence. Following standard procedure, you might contact a large Ford dealership, only to be told they can’t assist immediately due to recall commitments. Turning to a local Ford dealer offers no quicker solution, with appointment slots booked weeks in advance. Even your trusted local mechanic hesitates, admitting a lack of specialized diagnostic tools for intricate electrical faults. This leaves you, the car owner, in a diagnostic limbo.
In this situation, a DIY approach becomes almost necessary. Troubleshooting begins, often involving checking the usual suspects. In one such case, the focus shifted to the Front Control Module (FCM), located in the vehicle’s C-pillar. Upon inspection, the FCM connector appeared clean and undamaged. Yet, disconnecting and reconnecting it, followed by a gentle tap on the module, miraculously resolved the issue. The engine cranked and ran perfectly, idling smoothly for over an hour without any problems. Remarkably, throughout this entire ordeal – the initial no-crank, the temporary fix – the OBD2 system remained silent, reporting “no codes are stored in the module.” Subsequent restarts, even after letting the vehicle sit overnight, were also flawless.
The Plot Thickens: Inducing and Losing the Fault
Intrigued and slightly suspicious of such an easy fix, further investigation was warranted. Attempting to replicate the fault by wiggling and tapping the FCM connector proved unsuccessful. However, intentionally pulling the connector while the engine was running produced an immediate stall and, finally, illuminated the check engine light (CEL) along with a wrench symbol on the dashboard. This action did trigger codes, as expected.
This outcome raises a critical question: why did pulling the connector while running trigger a CEL and store codes, but the initial “failure” – the no-crank condition – did not? This discrepancy highlights a crucial aspect of OBD2 systems and intermittent faults. The lack of codes during the no-crank incident suggests that the fault might have been intermittent or not severe enough, in the system’s perception, to warrant storing a permanent DTC. It’s possible the issue was a marginal connection problem within the FCM connector, momentarily disrupted, then temporarily resolved by manipulation.
Recall Concerns and Diagnostic Uncertainty
Further research into the FCM part number revealed another layer of complexity. Comparison against a Ford recall notice https://www-odi.nhtsa.dot.gov/acms/cs/j … 1-3174.pdf indicated potential recall implications, particularly for Ecoboost engines, depending on specific part number suffixes. However, the most pressing concern remains the absence of diagnostic codes during the initial failure.
The “no codes stored” scenario, especially in a no-crank situation, can be unsettling. It breeds uncertainty and a lack of confidence in the vehicle’s reliability. Replacing parts based on a hunch is not ideal, especially without concrete diagnostic evidence. The fear of a recurring breakdown, potentially in a less convenient location, lingers. This case underscores the limitations of OBD2 systems in capturing all types of faults, particularly intermittent electrical issues. While OBD2 is invaluable for many diagnostic tasks, situations like this highlight the need for thorough physical inspections and potentially more advanced diagnostic techniques when faced with “no codes” and persistent vehicle problems. For further insights into OBD2 diagnostics and troubleshooting, explore more resources on obd-de.com.
