As a teen in the eighties and an owner of the ZX 81 and spectrum always wanted a C5. Now I have one. Struggling a bit with the electrics at the moment. The control box had obviously had a fire from a short previously. It pedals fine has has the original tyres. When I powered it up all the LEDs on both sides come on. Anbody have any ideas?

Hi there and welcome to the forum!

The problem with the LED's lighting up on the left (right-side should be fine if your battery is fully charged?) is probably down to your control box and one of the resistors (R1) or LM358 chip.  Are you able to inspect the circuit board and look for damage?

It could also be the ULA chip in the pod, but I'd start with the control box.

You may want to look at this post for pointers on repairing a control box:

Thanks 4 the reply. The circuit board has some damage from the fire. I will get the multimeter out again. The motor works when connected directly.
I connected it up to my car battery. When I reconnected the board all the leds came on but I couldn't get the relay to switch. The lights work. I am guessing that because it thinks the battery is overloaded then it is cut out.
I will put some pics up soon.

Finally got the circuirt board working today. However all the Leds are on all thetime. Anybody got any ideas?

Might be worth checking/cleaning the connection of the red pod wires mine gave me loads of problems.So I eventually got rid of the pod and control box.

Thanks I will try that

Hey
Often if the LEDs are all on the time, it could indeed be corrosion inside the red plug that plugs into the back of the pod. And/or corrosion on the 7 or 8 Pins on the pod itself.

Also could be dry solder joints on the pins on the pod.

What i do is remove the pod, unscrew it to get inside and then try inserting the red plug onto the pins but from Inside the pod (the pins are very long). Usually the pins on the inside of the pod are clean so you can do a test this way.

I then clean the red plug with a tooth brush and suitable cleaner (nothing that melts plastic), then dremmel with a fine wire brush the pod pins.

This has worked for me in the past. Otherwise it could be anything really (pod, red wire loom/control box) if you have access to a spare pod then try another pod.

Cheers!

Hi what I do is to use a pod connector that I have made just to eliminate the cable Then as Poze says check out the pins

We finally got it going, but the thermal cut out goes too quickly. Never mind did a few miles. Is it safe to disconnect the cutouts?

Is there any sign of heat when the cutout open circuits if not you could always replace the cutout rather than disconnecting it
It may just be faulty

No the motor is fine so I think the sensor or something on the board is faulty. It probably relatesbto the left hand side LEDs being permenantly on.

In that case I think you have no choice but to get it repaired or buy another

[quote=dadandjames;1430]No the motor is fine so I think the sensor or something on the board is faulty. It probably relatesbto the left hand side LEDs being permenantly on. [/quote]

Have you checked the LM358 chip in the control box?  That can cause the left LEDs to be permanently on.  Had that once myself. I've got a box of those chips here if you want one, you just need to unsolder the one in the cb and replace it (ideally putting a socket in first).

I am not sure how to check the chip out. I have checked r1 and that is ok as are the contacts. Can you mailme [email protected] with price of new chip, and do you have the details of the chip holder?
I am really grateful for your help.

I ve got a spare temperature sensor if you want one.

Hold on to it I will let you know

Ok will do .