Date: 201910
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 145 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
Airspace: Class C ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Door Warning System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Time Pressure
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Maintenance
Detector: Person Flight Crew
When detected: Taxi
Result: Aircraft Aircraft Damaged; Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Maintenance Action; General Flight Cancelled / Delayed
Contributing factors: MEL; Manuals; Procedure; Aircraft
Primary problem: MEL

Narrative: We boarded the aircraft without incident and pushed back from the gate. Before engine start; ATC informed us of a 2 1/2 hour delay before takeoff. We opted to return to the gate and deplane the passengers. After the delay; we boarded the aircraft and taxied for takeoff. It was a normal takeoff until about 60 to 70 kts. when we got a baggage door open caution message and aborted the takeoff. After clearing the runway I made a PA to the passengers to remain seated and the FO (First Officer) ran the immediate action items and QRH. We taxied back to the ramp and after about 20 minutes of continuous; unsuccessful attempts to contact ZZZ Operations; we were parked at the gate by the ramp personnel without ever making radio contact with them. I contacted Maintenance and we did a crew deferral over the phone for baggage door indication. Before we could even look at the baggage door; the ground crew opened it when we parked at the gate. I had no way to tell them not to before I looked at it since they never responded to the radio or repeated phone calls to ZZZ Operations. They told me it appeared to be closed and latched properly. Maintenance told me the aircraft is safe to operate per the MEL and to continue the flight with the baggage door indication deferred. After a conversation with my FO; we both agreed that we were not comfortable taking the aircraft after not having any confirmation of what caused the indication and having done nothing to isolate or fix the original problem. We both agreed that there was a good chance we'd get the caution message again on a subsequent takeoff. Several calls to Maintenance and the chief pilot led to me refusing the aircraft. The MEL provided no information on what to expect or what could be ignored operationally with the indication system deferred nor did it provide any method to isolate the indication from coming on again or forcing it to stay on. Maintenance informed me that we could take the aircraft and even ignore a caution message for baggage door open on takeoff since the system was deferred. This was not a satisfactory explanation for me since the MEL doesn't explicitly say we can do that. I understand that as it was written; the deferral process was satisfactory from a paperwork standpoint; but I felt we were in an ambiguous situation that required further clarification or procedures to ensure a safe operational environment. After several calls with Maintenance and assurance that the aircraft was safe; we agreed to take the aircraft under the understanding that if we got another indication on the takeoff roll of any kind; including the baggage door open indication; we would reject the takeoff as per operational specifications. After the delay; we took off without incident and did not get any baggage door indications during the flight.The obvious threat was a system failure during takeoff and undesired aircraft state was a rejected takeoff. Subsequent threats involved a deferral process that doesn't do anything to confirm that actual issue or isolate the problem from causing a disruption during critical phases of flight. This was highly unusual for me as my 11 years of flying the CRJ never saw me deferring a system with such ambiguity. Given the conditions (a strong crosswind) and no confirmation of the actual issue; the FO and I both believed there was a strong chance the issue would recur on the subsequent takeoff. No one had any way to know if the indication system was not operating properly or if the door latch was faulty as the deferral process didn't provide any method of determining that. The FO and I both initially believed that to be insufficient in determining the aircraft's airworthiness. After several conversations with the Company and an explanation of the MEL process and the Company's determination to opt out of the option to require the baggage door indication system to be secured; we decided that the aircraft was safe to fly in its current condition; even if the situation was less than ideal.It's my belief that we followed the operational specifications correctly. The company could update the MEL procedure to put the aircraft in a more secure condition to operate the flight without interruption; or update the instructions to include directions for what to do if the message re-appears in critical phases of flight. I was told that it was ok to ignore the message alerting us during the takeoff phase and I don't believe operation specs specifically allow me to do so without relief being indicated by the MEL itself. I recognize that this was a bit of an ambiguous situation and the intent of the MEL was followed properly; but there was no clear 'right' decision to make in this situation.




Synopsis: EMB-145 Captain reported a rejected takeoff for a cargo door warning light.