A spokesman for Merseytravel, which runs the Mersey Tunnels, said: "The barriers were lifted at 4.46pm and we apologise to anyone who had to wait. We will refund any money paid by the people at the frontofthe queue.
"We have no record of the emergency phones being used at all yesterday.
"Each and every phone was checked this morning and every single one is in full working order."
He added the incident was "a chance to review procedures," adding: "We think our system works, but that doesn't mean we can't learn lessons."
The tunnel was closed in both directions until 6.30pm while traffic was diverted to the Kingsway (Wallasey) Tunnel.
A spokeswoman for Merseyside Fire Service said: "We had four pumps on scene to put out the fire caused by a wiring fault in the Citroen.
* A series of safety measures, costing £7m, have been introduced in the Mersey Tunnels to bring them up to 21st century standard. They include three new escape tunnels, more escape passages and underground bunkers which can hold up to 980 people.
* Were you caught up in the drama? Contact Kate Mansey on 0151-2887635 or email kate.mansey@liverpool.com
Car on fire in Mersey tunnel
Were you caught up in the traffic chaos following the closure of the tunnel? Let us know - tell us about it here
Total chaos along Scotland Road there should be large signs advising traffic which tunnel to use when either tunnel is shut.There was nothing in place to steer clear of the Birkenhead tunnel around 1630-1700pm.I had to perform a U turn as did many other motorists.It was mayhem im suprised there wasnt any accidents.