Cable Modem Has Ethernet But WI-FI Router Does Not See It

[kc27]

I have Spectrum 300 Mbps service via my Netgear CM600 cable modem. The modem is connected to an Asus RT-AC88U wireless router. There is no internet connectivity via WI-FI from the router. The RT-AC88U's WAN indicator is red for "No IP or no physical connection". If I connected a PC to the modem directly via ethernet cable, I have connectivity.

I rebooted the modem and connected it to a DLink DIR-868L wireless router and have the same problem. The WI-FI does not have any internet connectivity. If I connect a computer to one of the router's LAN ports, I am connected to the interest.

Any ideas on why two different routers are not getting an internet connectivity from the modem? Is this a sign of a failed modem?

 

[kc27]

Ii sprayed DeoxIT D5 electronics cleaner on the ethernet cable connector and in the ethernet port on the modem and worked the cable connector in the port . Both routers got a signal after I did that. The fact that a computer directly connected to the modem worked prior to the cleaning makes me think the routers working after the cleaning was a coincidence, and I may have a failing modem. Spectrum provides modems at no charge. I am going to get one from them just to have it on hand as a back-up.

 

[thecheapseats]

Ii sprayed DeoxIT D5 electronics cleaner <snip> <snip> The fact that a computer directly connected to the modem worked prior to the cleaning <snip>

as for your perceived coincidence (computer direct to modem working) many times inserting any connector/interconnect will remove enough crud momentarily on a plated surface to establish a connection...

however - if you have physical metallic interconnects of any kind (computing - audio - video) you simply must have some Deoxit (red for old in service conns - gold for new conns) in your maintenance kit... just over 40 years ago a Caig field rep from San Diego walked into my business in L.A. and left samples of their Deoxit products... the stuff is freaking magic and I've been using it ever since on old and new install conns...

 

[Tech Junky]

None of this makes sense as the physical connection doesn't affect the WIFI portion of 2 routers.

The fact that a direct connection either PC or Router works just fine rules this out.

I highly doubt the issue is the CM at this point. Now, why the PC works when on Ethernet and not WIFI kind of points to an issue on the PC WIFI card if anything else if it hasn't been tested to be working on any other SSID.

1st issue seems to be an Asus problem w/ the POS not getting an IP from the CM for whatever reason. Reset it with a hard reset and reconfigure and try again. If it fails then toss it in the bin and get something else.

2nd issue is the DL works on wired but not for WIFI which leads back to the PC having a potentially bad card.

 

[thecheapseats]

OP stated, "The RT-AC88U's WAN indicator is red for "No IP or no physical connection". If I connected a PC to the modem directly via ethernet cable, I have connectivity."...

which brings into question the original ethernet physical conn between the router and the modem... there may be a wi-fi issue as well - but you gotta' confirm a reliable wan connection at the start of the troubleshooting process...

 

[Tech Junky]

OP stated, "The RT-AC88U's WAN indicator is red for "No IP or no physical connection". If I connected a PC to the modem directly via ethernet cable, I have connectivity."...

which brings into question the original ethernet physical conn between the router and the modem... there may be a wi-fi issue as well - but you gotta' confirm a reliable wan connection at the start of the troubleshooting process...

Or, as stated the Asus is dead / dying and the DLINK works fine except for WIFI which leads to the PC WIFI card.

Physical port on the CM is working fine as diagnosed with direct PC connection and DLINK.

 

[thecheapseats]

OP never stated he had functioning wi-fi (only functioning hard wire) after each router established a wan conn... so not enough info from OP at this point...

given the history of ac86 routers - I'd bet that may likely the problem... UNLESS the OP has functioning wi-fi now - which he hasn't indicated one way or the other...

he has enough info to troubleshoot the problem...

 

[PunchCardBoss]

OP never stated he had functioning wi-fi (only functioning hard wire)

Remember, the RT-AC88U has a WIFI On/Off button on the lower right side that is soooo easy to push by mistake.

Last time I accidently pushed the WIFI button off, it took me hours to figure out what went wrong. If I remember correctly, pushing the button sets the GUI WiFi settings to OFF. So on re-boot, still no WiFi. I only noticed this condition when checking the GUI.

Meanwhile, all ethernet wired ports worked just fine.

 

[thecheapseats]

Remember, the RT-AC88U has a WIFI On/Off button on the lower right side that is soooo easy to push by mistake.

Last time I accidently pushed the WIFI button off, it took me hours to figure out what went wrong. If I remember correctly, pushing the button sets the GUI WiFi settings to OFF. So on re-boot, still no WiFi. I only noticed this condition when checking the GUI.

Meanwhile, all ethernet wired ports worked just fine.

yep - certainly could be that...