Can ISP check router settings?

I'm currently experiencing an outage with SSE broadband. I was using my own TP-Link router instead of the Technicolour one they provided.

In the course of the conversation I had with them, they said I'd need to use their router so they could run some further checks. I'm sure they only wanted me to tell them which lights were on, but is there any further checks that an ISP can do against the router they provide?

I work in IT, so I suspect this was just another way for them to fob me off.

Take a look at TR-069, remote config and management for provider supplied hardware

In reply to a post by messyhead:

In the course of the conversation I had with them, they said I'd need to use their router so they could run some further checks. I'm sure they only wanted me to tell them which lights were on, but is there any further checks that an ISP can do against the router they provide?

Any number of them. They can even push firmware updates.

Now whether such access is actually worthwhile in diagnosing a fault is a different thing. I've always been sceptical of the idea that ISP support staff would be capable of gleaning anything useful that way. Most faults are electrical in nature and dealt with by openreach who have no interest in your router. The kinds of faults where router access would be useful are the kind of things that ISP support staff are unlikely to want to get involved in like port forwarding.

One advantage of using an ISP supplied router in a fault scenario is that it gives the ISP a known DSL chipset and firmware to troubleshoot with. As a recent post in the Zen forum mentions, symptoms such as packet loss can be down to firmware issues, as can lower level DSL problems that might look like a fault.

It also can give them a known configuration - who knows what tweaks someone might have made to the config of a router that the ISP doesn't have experience of. Once you can rule out everything out of the ISPs control then the problem becomes the ISPs - as long as there is anything else in the loop then there is room for ambiguity.